Merge remote-tracking branch 'origin/master'

20 files changed, 1336 insertions, 661 deletions

diff --git a/src/bp_sim.cpp b/src/bp_sim.cpp
index 081553b5..6342b7f3 100755
--- a/src/bp_sim.cpp
+++ b/src/bp_sim.cpp
@@ -3146,7 +3146,7 @@ int CNodeGenerator::open_file(std::string file_name,
     /* ser preview mode */
     m_v_if->set_review_mode(preview_mode);
     m_v_if->open_file(file_name);
-    m_cnt = 1;
+    m_cnt = 0;
     return (0);
 }
 
@@ -3159,11 +3159,13 @@ int CNodeGenerator::close_file(CFlowGenListPerThread * thread){
 }
 
 int CNodeGenerator::update_stl_stats(CGenNodeStateless *node_sl){
+    m_cnt++;
+
     if ( m_preview_mode.getVMode() >2 ){
         fprintf(stdout," %4lu ,", (ulong)m_cnt);
         node_sl->Dump(stdout);
-        m_cnt++;
     }
+
     return (0);
 }
 
@@ -3199,7 +3201,9 @@ bool CFlowGenListPerThread::Create(uint32_t           thread_id,
 
     char name[100];
     sprintf(name,"nodes-%d",m_core_id);
-    printf(" create thread %d %s socket: %d \n",m_core_id,name,socket_id);
+
+    //printf(" create thread %d %s socket: %d \n",m_core_id,name,socket_id);
+
     m_node_pool = utl_rte_mempool_create_non_pkt(name,
                                                  CGlobalInfo::m_memory_cfg.get_each_core_dp_flows(), 
                                                  sizeof(CGenNode),
@@ -3207,7 +3211,8 @@ bool CFlowGenListPerThread::Create(uint32_t           thread_id,
                                                  0 ,
                                                  socket_id);
 
-    printf(" pool %p \n",m_node_pool);
+    //printf(" pool %p \n",m_node_pool);
+
     m_node_gen.Create(this);
     m_flow_id_to_node_lookup.Create();
 
diff --git a/src/internal_api/trex_platform_api.h b/src/internal_api/trex_platform_api.h
index 343b8004..3ae49da8 100644
--- a/src/internal_api/trex_platform_api.h
+++ b/src/internal_api/trex_platform_api.h
@@ -138,7 +138,7 @@ public:
  */
 class TrexMockPlatformApi : public TrexPlatformApi {
 public:
-    void port_id_to_cores(uint8_t port_id, std::vector<std::pair<uint8_t, uint8_t>> &cores_id_list) const {}
+    void port_id_to_cores(uint8_t port_id, std::vector<std::pair<uint8_t, uint8_t>> &cores_id_list) const;
     void get_global_stats(TrexPlatformGlobalStats &stats) const;
     void get_interface_stats(uint8_t interface_id, TrexPlatformInterfaceStats &stats) const;
     void get_interface_info(uint8_t interface_id, std::string &driver_name, driver_speed_e &speed) const {
diff --git a/src/main.cpp b/src/main.cpp
index 1b219a8c..ba6e258a 100755
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -23,16 +23,34 @@ limitations under the License.
 #include "bp_sim.h"
 #include "os_time.h"
 
+#include <string>
 
 #include <common/arg/SimpleGlob.h>
 #include <common/arg/SimpleOpt.h>
 #include <stateless/cp/trex_stateless.h>
+#include <sim/trex_sim.h>
 
+using namespace std;
 
 // An enum for all the option types
 enum { OPT_HELP, OPT_CFG, OPT_NODE_DUMP, OP_STATS,
-          OPT_FILE_OUT, OPT_UT, OPT_PCAP, OPT_IPV6, OPT_MAC_FILE};
-      
+       OPT_FILE_OUT, OPT_UT, OPT_PCAP, OPT_IPV6, OPT_MAC_FILE,
+       OPT_SL, OPT_DP_CORE_COUNT, OPT_DP_CORE_INDEX};
+
+
+
+/**
+ * type of run 
+ * GTEST 
+ * Stateful 
+ * Stateless 
+ */
+typedef enum {
+    OPT_TYPE_GTEST = 7,
+    OPT_TYPE_SF,
+    OPT_TYPE_SL
+} opt_type_e;
+
 
 /* these are the argument types:
    SO_NONE --    no argument needed
@@ -41,17 +59,20 @@ enum { OPT_HELP, OPT_CFG, OPT_NODE_DUMP, OP_STATS,
 */
 static CSimpleOpt::SOption parser_options[] =
 {
-    { OPT_HELP,     "-?",           SO_NONE   },
-    { OPT_HELP,     "-h",           SO_NONE   },
-    { OPT_HELP,     "--help",       SO_NONE   },
-    { OPT_UT,       "--ut",         SO_NONE   },
-    { OP_STATS,       "-s",         SO_NONE   },
-    { OPT_CFG,      "-f",           SO_REQ_SEP},
-    { OPT_MAC_FILE, "--mac",        SO_REQ_SEP},
-    { OPT_FILE_OUT , "-o",          SO_REQ_SEP },
-    { OPT_NODE_DUMP , "-v",         SO_REQ_SEP },
-    { OPT_PCAP,       "--pcap",       SO_NONE   },
-    { OPT_IPV6,       "--ipv6",       SO_NONE   },
+    { OPT_HELP,          "-?",           SO_NONE    },
+    { OPT_HELP,          "-h",           SO_NONE    },
+    { OPT_HELP,          "--help",       SO_NONE    },
+    { OPT_UT,            "--ut",         SO_NONE    },
+    { OP_STATS,          "-s",           SO_NONE    },
+    { OPT_CFG,           "-f",           SO_REQ_SEP },
+    { OPT_MAC_FILE,      "--mac",        SO_REQ_SEP },
+    { OPT_FILE_OUT ,     "-o",           SO_REQ_SEP },
+    { OPT_NODE_DUMP ,    "-v",           SO_REQ_SEP },
+    { OPT_PCAP,          "--pcap",       SO_NONE    },
+    { OPT_IPV6,          "--ipv6",       SO_NONE    },
+    { OPT_SL,            "--sl",         SO_NONE    },
+    { OPT_DP_CORE_COUNT, "--cores",      SO_REQ_SEP },
+    { OPT_DP_CORE_INDEX, "--core_index", SO_REQ_SEP },
 
     
     SO_END_OF_OPTIONS
@@ -94,9 +115,14 @@ static int usage(){
     return (0);
 }
 
-int gtest_main(int argc, char **argv) ;
 
-static int parse_options(int argc, char *argv[], CParserOption* po, bool & is_gtest ) {
+static int parse_options(int argc,
+                         char *argv[],
+                         CParserOption* po,
+                         opt_type_e &type,
+                         int &dp_core_count,
+                         int &dp_core_index) {
+
      CSimpleOpt args(argc, argv, parser_options);
 
      int a=0;
@@ -104,36 +130,62 @@ static int parse_options(int argc, char *argv[], CParserOption* po, bool & is_gt
      po->preview.clean();
      po->preview.setFileWrite(true);
 
+     /* by default - type is stateful */
+     type = OPT_TYPE_SF;
+
+     dp_core_count = 1;
+     dp_core_index = 0;
+
      while ( args.Next() ){
         if (args.LastError() == SO_SUCCESS) {
             switch (args.OptionId()) {
             case OPT_UT :
-                is_gtest=true;
+                type = OPT_TYPE_GTEST;
                 return (0);
                 break;
+
             case OPT_HELP: 
                 usage();
                 return -1;
+
+            case OPT_SL:
+                type = OPT_TYPE_SL;
+                break;
+
             case OPT_CFG:
                 po->cfg_file = args.OptionArg();
                 break;
+
             case OPT_MAC_FILE:
                 po->mac_file = args.OptionArg();
                 break;
+
             case OPT_FILE_OUT:
                 po->out_file = args.OptionArg();
                 break;
+
             case OPT_IPV6:
                 po->preview.set_ipv6_mode_enable(true);
                 break;
+
             case OPT_NODE_DUMP:
                 a=atoi(args.OptionArg());
                 node_dump=1;
                 po->preview.setFileWrite(false);
                 break;
+
             case OPT_PCAP:
                 po->preview.set_pcap_mode_enable(true);
                 break;
+
+            case OPT_DP_CORE_COUNT:
+                dp_core_count = atoi(args.OptionArg());
+                break;
+
+            case OPT_DP_CORE_INDEX:
+                dp_core_index = atoi(args.OptionArg());
+                break;
+
             default:
                 usage();
                 return -1;
@@ -162,640 +214,54 @@ static int parse_options(int argc, char *argv[], CParserOption* po, bool & is_gt
          return -1;
         }
     }
-    return 0;
-}
-
-int cores=1;
-
-/*
-
-int curent_time(){
-
-	time_init();
-
-	int i;
-	for (i=0; i<100000000; i++){
-	  now=now_sec();
-	}
-	return (0);
-}*/
-
-#ifdef LINUX
-
-
-
-#include <pthread.h>
-
-struct per_thread_t {
-    pthread_t  tid;
-};
-
-#define MAX_THREADS 200
-static per_thread_t  tr_info[MAX_THREADS];
-
-
-//////////////
-
-struct test_t_info1 {
-    CPreviewMode *            preview_info;
-    CFlowGenListPerThread   * thread_info;
-    uint32_t                  thread_id;
-};
-
-void * thread_task(void *info){
-
-    test_t_info1 * obj =(test_t_info1 *)info;
-
-    CFlowGenListPerThread   * lpt=obj->thread_info;
-
-    printf("start thread %d \n",obj->thread_id);
-    //delay(obj->thread_id *3000);
-    printf("-->start thread %d \n",obj->thread_id);
-    if (1/*obj->thread_id ==3*/) {
-
-        char buf[100];
-        sprintf(buf,"my%d.erf",obj->thread_id);
-        lpt->start_generate_stateful(buf,*obj->preview_info);
-        lpt->m_node_gen.DumpHist(stdout);
-        printf("end thread %d \n",obj->thread_id);
-    }
-
-    return (NULL);
-}
-
-
-void test_load_list_of_cap_files_linux(CParserOption * op){
-
-    CFlowGenList fl;
-    //CNullIF erf_vif;
-    //CErfIF erf_vif;
-
-    fl.Create();
-
-    fl.load_from_yaml(op->cfg_file,cores);
-    fl.DumpPktSize();
-
-    
-    fl.generate_p_thread_info(cores);
-    CFlowGenListPerThread   * lpt;
-
-    /* set the ERF file */
-    //fl.set_vif_all(&erf_vif);
-
-    int i;
-    for (i=0; i<cores; i++) {
-        lpt=fl.m_threads_info[i];
-        test_t_info1 * obj = new test_t_info1();
-        obj->preview_info =&op->preview;
-        obj->thread_info  = fl.m_threads_info[i];
-        obj->thread_id    = i;
-        CNullIF * erf_vif = new CNullIF();
-        //CErfIF  * erf_vif = new CErfIF();
-
-        lpt->set_vif(erf_vif);
-
-        assert(pthread_create( &tr_info[i].tid, NULL, thread_task, obj)==0);
-    }
-
-    for (i=0; i<cores; i++) {
-        /* wait for all of them to stop */
-       assert(pthread_join((pthread_t)tr_info[i].tid,NULL )==0);
-    }
-
-    printf("compare files \n");
-    for (i=1; i<cores; i++) {
-
-        CErfCmp cmp;
-        char buf[100];
-        sprintf(buf,"my%d.erf",i);
-        char buf1[100];
-        sprintf(buf1,"my%d.erf",0);
-        if ( cmp.compare(std::string(buf),std::string(buf1)) != true ) {
-            printf(" ERROR cap file is not ex !! \n");
-            assert(0);
-        }
-        printf(" thread %d is ok \n",i);
-    }
-
-    fl.Delete();
-}
-
-
-#endif
-
-/*************************************************************/
-void test_load_list_of_cap_files(CParserOption * op){
-
-    CFlowGenList fl;
-    CNullIF erf_vif;
-
-    fl.Create();
-
-    #define NUM 1
-
-    fl.load_from_yaml(op->cfg_file,NUM);
-    fl.DumpPktSize();
-    
-    
-    fl.generate_p_thread_info(NUM);
-    CFlowGenListPerThread   * lpt;
-
-    /* set the ERF file */
-    //fl.set_vif_all(&erf_vif);
-
-    int i;
-    for (i=0; i<NUM; i++) {
-        lpt=fl.m_threads_info[i];
-        char buf[100];
-        sprintf(buf,"my%d.erf",i);
-        lpt->start_generate_stateful(buf,op->preview);
-        lpt->m_node_gen.DumpHist(stdout);
-    }
-    //sprintf(buf,"my%d.erf",7);
-    //lpt=fl.m_threads_info[7];
-
-    //fl.Dump(stdout);
-    fl.Delete();
-}
-
-int load_list_of_cap_files(CParserOption * op){
-    CFlowGenList fl;
-    fl.Create();
-    fl.load_from_yaml(op->cfg_file,1);
-    if ( op->preview.getVMode() >0 ) {
-        fl.DumpCsv(stdout);
-    }
-    uint32_t start=    os_get_time_msec();
-
-    CErfIF erf_vif;
-    //CNullIF erf_vif;
-
-    fl.generate_p_thread_info(1);
-    CFlowGenListPerThread   * lpt;
-    lpt=fl.m_threads_info[0];
-    lpt->set_vif(&erf_vif);
-
-    if ( (op->preview.getVMode() >1)  || op->preview.getFileWrite() ) {
-        lpt->start_generate_stateful(op->out_file,op->preview);
-    }
-
-    lpt->m_node_gen.DumpHist(stdout);
 
-    uint32_t stop=    os_get_time_msec();
-    printf(" d time = %ul %ul \n",stop-start,os_get_time_freq());
-    fl.Delete();
-    return (0);
-}
-
-
-int test_dns(){
-
-    time_init();
-    CGlobalInfo::init_pools(1000);
-
-    CParserOption po ;
-
-    //po.cfg_file = "cap2/dns.yaml";
-    //po.cfg_file = "cap2/sfr3.yaml";
-    po.cfg_file = "cap2/sfr.yaml";
-
-    po.preview.setVMode(0);
-    po.preview.setFileWrite(true);
-    #ifdef LINUX
-      test_load_list_of_cap_files_linux(&po);
-    #else
-      test_load_list_of_cap_files(&po);
-    #endif
-    return (0);
-}
-
-void test_pkt_mbuf(void);
-
-void test_compare_files(void);
-
-#if 0
-static int b=0;
-static int c=0;
-static int d=0;
-
-int test_instructions(){
-    int i;
-    for (i=0; i<100000;i++) {
-        b+=b+1;
-        c+=+b+c+1;
-        d+=+(b*2+1);
-    }
-    return (b+c+d);
-}
-
-#include <valgrind/callgrind.h>
-#endif
-
-
-void update_tcp_seq_num(CCapFileFlowInfo * obj,
-                        int pkt_id,
-                        int size_change){
-    CFlowPktInfo * pkt=obj->GetPacket(pkt_id);
-    if ( pkt->m_pkt_indication.m_desc.IsUdp() ){
-        /* nothing to do */
-        return;
-    }
-
-    bool o_init=pkt->m_pkt_indication.m_desc.IsInitSide();
-    TCPHeader * tcp ;
-    int s= (int)obj->Size();
-    int i;
-
-    for (i=pkt_id+1; i<s; i++) {
-
-        pkt=obj->GetPacket(i);
-        tcp=pkt->m_pkt_indication.l4.m_tcp;
-        bool init=pkt->m_pkt_indication.m_desc.IsInitSide();
-        if (init == o_init) {
-            /* same dir update the seq number */
-            tcp->setSeqNumber    (tcp->getSeqNumber    ()+size_change);
-
-        }else{
-            /* update the ack number */
-            tcp->setAckNumber    (tcp->getAckNumber    ()+size_change);
+    if (dp_core_count != -1) {
+        if ( (dp_core_count < 1) || (dp_core_count > 8) ) {
+            printf("dp core count must be a value between 1 and 8\n");
+            return (-1);
         }
     }
-}
-
-
-
-void change_pkt_len(CCapFileFlowInfo * obj,int pkt_id, int size ){
-    CFlowPktInfo * pkt=obj->GetPacket(pkt_id);
 
-    /* enlarge the packet size by 9 */
-
-    char * p=pkt->m_packet->append(size);
-    /* set it to 0xaa*/
-    memmove(p+size-4,p-4,4); /* CRCbytes */
-    memset(p-4,0x0a,size);
-
-    /* refresh the pointers */
-    pkt->m_pkt_indication.RefreshPointers();
-
-    IPHeader       * ipv4 = pkt->m_pkt_indication.l3.m_ipv4;
-    ipv4->updateTotalLength	(ipv4->getTotalLength()+size );
-
-    /* update seq numbers if needed */
-    update_tcp_seq_num(obj,pkt_id,size);
-}
-
-void dump_tcp_seq_num_(CCapFileFlowInfo * obj){
-    int s= (int)obj->Size();
-    int i;
-    uint32_t i_seq;
-    uint32_t r_seq;
-
-    CFlowPktInfo * pkt=obj->GetPacket(0);
-    TCPHeader * tcp = pkt->m_pkt_indication.l4.m_tcp;
-    i_seq=tcp->getSeqNumber    ();
-
-    pkt=obj->GetPacket(1);
-    tcp = pkt->m_pkt_indication.l4.m_tcp;
-    r_seq=tcp->getSeqNumber    ();
-
-    for (i=2; i<s; i++) {
-        uint32_t seq;
-        uint32_t ack;
-
-        pkt=obj->GetPacket(i);
-        tcp=pkt->m_pkt_indication.l4.m_tcp;
-        bool init=pkt->m_pkt_indication.m_desc.IsInitSide();
-        seq=tcp->getSeqNumber    ();
-        ack=tcp->getAckNumber    ();
-        if (init) {
-            seq=seq-i_seq;
-            ack=ack-r_seq;
-        }else{
-            seq=seq-r_seq;
-            ack=ack-i_seq;
+     if (dp_core_index != -1) {
+        if ( (dp_core_index < 0) || (dp_core_index >= dp_core_count) ) {
+            printf("dp core count must be a value between 0 and cores - 1\n");
+            return (-1);
         }
-        printf(" %4d ",i);
-        if (!init) {
-            printf("                             ");
-        }
-        printf("  %s   seq: %4d   ack : %4d   \n",init?"I":"R",seq,ack);
     }
-}
 
-
-int manipolate_capfile() {
-    time_init();
-    CGlobalInfo::init_pools(1000);
-
-    CCapFileFlowInfo flow_info;
-    flow_info.Create();
-
-    flow_info.load_cap_file("avl/delay_10_rtsp_0.pcap",0,0);
-
-    change_pkt_len(&flow_info,4-1 ,6);
-    change_pkt_len(&flow_info,5-1 ,6);
-    change_pkt_len(&flow_info,6-1 ,6+2);
-    change_pkt_len(&flow_info,7-1 ,4);
-    change_pkt_len(&flow_info,8-1 ,6+2);
-    change_pkt_len(&flow_info,9-1 ,4);
-    change_pkt_len(&flow_info,10-1,6);
-    change_pkt_len(&flow_info,13-1,6);
-    change_pkt_len(&flow_info,16-1,6);
-    change_pkt_len(&flow_info,19-1,6);
-
-    flow_info.save_to_erf("exp/c.pcap",1);
-    
-    return (1);
-}
-
-int manipolate_capfile_sip() {
-    time_init();
-    CGlobalInfo::init_pools(1000);
-
-    CCapFileFlowInfo flow_info;
-    flow_info.Create();
-
-    flow_info.load_cap_file("avl/delay_10_sip_0.pcap",0,0);
-
-    change_pkt_len(&flow_info,1-1 ,6+6);
-    change_pkt_len(&flow_info,2-1 ,6+6);
-
-    flow_info.save_to_erf("exp/delay_10_sip_0_fixed.pcap",1);
-    
-    return (1);
-}
-
-int manipolate_capfile_sip1() {
-    time_init();
-    CGlobalInfo::init_pools(1000);
-
-    CCapFileFlowInfo flow_info;
-    flow_info.Create();
-
-    flow_info.load_cap_file("avl/delay_sip_0.pcap",0,0);
-    flow_info.GetPacket(1);
-
-    change_pkt_len(&flow_info,1-1 ,6+6+10);
-
-    change_pkt_len(&flow_info,2-1 ,6+6+10);
-
-    flow_info.save_to_erf("exp/delay_sip_0_fixed_1.pcap",1);
-    
-    return (1);
-}
-
-
-class CMergeCapFileRec {
-public:
-
-    CCapFileFlowInfo m_cap;
-
-    int              m_index;
-    int              m_limit_number_of_packets; /* limit number of packets */
-    bool             m_stop; /* Do we have more packets */
-
-    double           m_offset; /* offset should be positive */
-    double           m_start_time;
-
-public:
-    bool Create(std::string cap_file,double offset);
-    void Delete();
-    void IncPacket();
-    bool GetCurPacket(double & time);
-    CPacketIndication *  GetUpdatedPacket();
-
-    void Dump(FILE *fd,int _id);
-};
-
-
-void CMergeCapFileRec::Dump(FILE *fd,int _id){
-    double time = 0.0;
-    bool stop=GetCurPacket(time);
-    fprintf (fd," id:%2d  stop : %d index:%4d  %3.4f \n",_id,stop?1:0,m_index,time);
-}
-
-
-CPacketIndication *  CMergeCapFileRec::GetUpdatedPacket(){
-    double t1;
-    assert(GetCurPacket(t1)==false);
-    CFlowPktInfo * pkt = m_cap.GetPacket(m_index);
-    pkt->m_pkt_indication.m_packet->set_new_time(t1);
-    return (&pkt->m_pkt_indication);
+    return 0;
 }
 
 
-bool  CMergeCapFileRec::GetCurPacket(double & time){
-    if (m_stop) {
-        return(true);
-    }
-    CFlowPktInfo * pkt = m_cap.GetPacket(m_index);
-    time= (pkt->m_packet->get_time() -m_start_time + m_offset);
-    return (false);
-}
+int main(int argc , char * argv[]){
 
-void CMergeCapFileRec::IncPacket(){
-    m_index++;
-    if ( (m_limit_number_of_packets) && (m_index > m_limit_number_of_packets ) ) {
-        m_stop=true;
-        return;
-    }
+    opt_type_e type;
+    int dp_core_count;
+    int dp_core_index;
 
-    if ( m_index == (int)m_cap.Size() ) {
-        m_stop=true;
+    if ( parse_options(argc, argv, &CGlobalInfo::m_options , type, dp_core_count, dp_core_index) != 0) {
+        exit(-1);
     }
-}
-
-void CMergeCapFileRec::Delete(){
-    m_cap.Delete();
-}
-
-bool CMergeCapFileRec::Create(std::string cap_file,
-                              double offset){
-   m_cap.Create();
-   m_cap.load_cap_file(cap_file,0,0);
-   CFlowPktInfo * pkt = m_cap.GetPacket(0);
-
-   m_index=0;
-   m_stop=false;
-   m_limit_number_of_packets =0;
-   m_start_time =     pkt->m_packet->get_time() ;
-   m_offset = offset;
-
-   return (true);
-}
-
 
-
-#define MERGE_CAP_FILES (2)
-
-class CMergeCapFile {
-public:
-    bool Create();
-    void Delete();
-    bool run_merge(std::string to_cap_file);
-private:
-    void append(int _cap_id);
-
-public:
-    CMergeCapFileRec m[MERGE_CAP_FILES];
-    CCapFileFlowInfo m_results;
-};
-
-bool CMergeCapFile::Create(){
-    m_results.Create();
-    return(true);
-}
-
-void CMergeCapFile::Delete(){
-    m_results.Delete();
-}
-
-void CMergeCapFile::append(int _cap_id){
-    CPacketIndication * lp=m[_cap_id].GetUpdatedPacket();
-    lp->m_packet->Dump(stdout,0);
-    m_results.Append(lp);
-}
-
-
-bool CMergeCapFile::run_merge(std::string to_cap_file){
-
-    int i=0;
-    int cnt=0;
-    while ( true ) {
-        int    min_index=0;
-        double min_time;
-
-        fprintf(stdout," --------------\n");
-        fprintf(stdout," pkt : %d \n",cnt);
-        for (i=0; i<MERGE_CAP_FILES; i++) {
-            m[i].Dump(stdout,i);
-        }
-        fprintf(stdout," --------------\n");
-
-        bool valid = false;
-        for (i=0; i<MERGE_CAP_FILES; i++) {
-            double t1;
-            if ( m[i].GetCurPacket(t1) == false ){
-                /* not in stop */
-                if (!valid) {
-                    min_time  = t1;
-                    min_index = i;
-                    valid=true;
-                }else{
-                    if (t1 < min_time) {
-                        min_time=t1;
-                        min_index = i;
-                    }
-                }
-
-            }
+    switch (type) {
+    case OPT_TYPE_GTEST:
+        {
+            SimGtest test;
+            return test.run(argc, argv);
         }
 
-        /* nothing to do */
-        if (valid==false) {
-            fprintf(stdout,"nothing to do \n");
-            break;
+    case OPT_TYPE_SF:
+        {
+            SimStateful sf;
+            return sf.run();
         }
 
-        cnt++;
-        fprintf(stdout," choose id %d \n",min_index);
-        append(min_index);
-        m[min_index].IncPacket();
-    };
-
-    m_results.save_to_erf(to_cap_file,1);
-
-    return (true);
-}
-
-
-
-int merge_3_cap_files() {
-    time_init();
-    CGlobalInfo::init_pools(1000);
-
-    CMergeCapFile merger;
-    merger.Create();
-    merger.m[0].Create("exp/c.pcap",0.001);
-    merger.m[1].Create("avl/delay_10_rtp_160k_0.pcap",0.31);
-    merger.m[2].Create("avl/delay_10_rtp_160k_1.pcap",0.311);
-
-    //merger.m[1].Create("avl/delay_10_rtp_250k_0_0.pcap",0.31);
-    //merger.m[1].m_limit_number_of_packets =6;
-    //merger.m[2].Create("avl/delay_10_rtp_250k_1_0.pcap",0.311);
-    //merger.m[2].m_limit_number_of_packets =6;
-
-    merger.run_merge("exp/delay_10_rtp_160k_full.pcap");
-
-    return (0);
-}
-
-int merge_2_cap_files_sip() {
-    time_init();
-    CGlobalInfo::init_pools(1000);
-
-    CMergeCapFile merger;
-    merger.Create();
-    merger.m[0].Create("exp/delay_sip_0_fixed_1.pcap",0.001);
-    merger.m[1].Create("avl/delay_video_call_rtp_0.pcap",0.51);
-    //merger.m[1].m_limit_number_of_packets=7;
-
-    //merger.m[1].Create("avl/delay_10_rtp_250k_0_0.pcap",0.31);
-    //merger.m[1].m_limit_number_of_packets =6;
-    //merger.m[2].Create("avl/delay_10_rtp_250k_1_0.pcap",0.311);
-    //merger.m[2].m_limit_number_of_packets =6;
-
-    merger.run_merge("avl/delay_10_sip_video_call_full.pcap");
-
-    return (0);
-}
-
-static TrexStateless *g_trex_stateless;
-
-
-TrexStateless * get_stateless_obj() {
-    return g_trex_stateless;
-}
-
-extern "C" const char * get_build_date(void){ 
-    return (__DATE__);
-}      
- 
-extern "C" const char * get_build_time(void){ 
-    return (__TIME__ );
-} 
-
-
-
-
-int main(int argc , char * argv[]){
-
-    int res=0;
-    time_init();
-    CGlobalInfo::m_socket.Create(0);
-    CGlobalInfo::init_pools(1000);
-    assert( CMsgIns::Ins()->Create(4) );
-
-
-    bool is_gtest=false;
-
-    if ( parse_options(argc, argv, &CGlobalInfo::m_options , is_gtest) != 0){
-        exit(-1);
-    }
-
-    if ( is_gtest ) {
-        res = gtest_main(argc, argv);
-    }else{
-        res = load_list_of_cap_files(&CGlobalInfo::m_options);
+    case OPT_TYPE_SL:
+        {
+            SimStateless &st = SimStateless::get_instance();
+            return st.run(CGlobalInfo::m_options.cfg_file, CGlobalInfo::m_options.out_file, 2, dp_core_count, dp_core_index);
+        }
     }
-
-    CMsgIns::Ins()->Free();
-    CGlobalInfo::free_pools();
-    CGlobalInfo::m_socket.Delete();
-
-
-    return (res);
-    
 }
 
 
diff --git a/src/mock/trex_platform_api_mock.cpp b/src/mock/trex_platform_api_mock.cpp
index 54f71e10..416c4b69 100644
--- a/src/mock/trex_platform_api_mock.cpp
+++ b/src/mock/trex_platform_api_mock.cpp
@@ -47,3 +47,7 @@ TrexMockPlatformApi::get_dp_core_count() const {
     return (1);
 }
 
+void 
+TrexMockPlatformApi::port_id_to_cores(uint8_t port_id, std::vector<std::pair<uint8_t, uint8_t>> &cores_id_list) const {
+    cores_id_list.push_back(std::make_pair(0, 0));
+}
diff --git a/src/mock/trex_rpc_server_mock.cpp b/src/mock/trex_rpc_server_mock.cpp
index 0bdf6cf1..ecfa308d 100644
--- a/src/mock/trex_rpc_server_mock.cpp
+++ b/src/mock/trex_rpc_server_mock.cpp
@@ -78,10 +78,6 @@ find_free_tcp_port(uint16_t start_port = 5050) {
     return port;
 }
 
-TrexStateless * get_stateless_obj() {
-    return g_trex_stateless;
-}
-
 uint16_t gtest_get_mock_server_port() {
     return g_rpc_port;
 }
diff --git a/src/publisher/trex_publisher.h b/src/publisher/trex_publisher.h
index bd4392f7..52978476 100644
--- a/src/publisher/trex_publisher.h
+++ b/src/publisher/trex_publisher.h
@@ -34,9 +34,11 @@ public:
         m_publisher = NULL;
     }
 
-    bool Create(uint16_t port, bool disable);
-    void Delete();
-    void publish_json(const std::string &s);
+    virtual ~TrexPublisher() {}
+
+    virtual bool Create(uint16_t port, bool disable);
+    virtual void Delete();
+    virtual void publish_json(const std::string &s);
 
     enum event_type_e {
         EVENT_PORT_STARTED          = 0,
@@ -51,7 +53,7 @@ public:
         
     };
 
-    void publish_event(event_type_e type, const Json::Value &data = Json::nullValue);
+    virtual void publish_event(event_type_e type, const Json::Value &data = Json::nullValue);
 
 private:
     void show_zmq_last_error(const std::string &err);
diff --git a/src/rpc-server/trex_rpc_async_server.cpp b/src/rpc-server/trex_rpc_async_server.cpp
index 46fe499b..6e5fbfc6 100644
--- a/src/rpc-server/trex_rpc_async_server.cpp
+++ b/src/rpc-server/trex_rpc_async_server.cpp
@@ -41,6 +41,10 @@ TrexRpcServerAsync::TrexRpcServerAsync(const TrexRpcServerConfig &cfg, std::mute
     m_context = zmq_ctx_new();
 }
 
+void
+TrexRpcServerAsync::_prepare() {
+}
+
 /**
  * publisher thread
  * 
diff --git a/src/rpc-server/trex_rpc_async_server.h b/src/rpc-server/trex_rpc_async_server.h
index 02d1490e..80d92c2f 100644
--- a/src/rpc-server/trex_rpc_async_server.h
+++ b/src/rpc-server/trex_rpc_async_server.h
@@ -36,6 +36,7 @@ public:
     TrexRpcServerAsync(const TrexRpcServerConfig &cfg, std::mutex *lock = NULL);
 
 protected:
+    void _prepare();
     void _rpc_thread_cb();
     void _stop_rpc_thread();
 
diff --git a/src/rpc-server/trex_rpc_cmd.cpp b/src/rpc-server/trex_rpc_cmd.cpp
index b5dd121c..aea7980b 100644
--- a/src/rpc-server/trex_rpc_cmd.cpp
+++ b/src/rpc-server/trex_rpc_cmd.cpp
@@ -32,7 +32,7 @@ TrexRpcCommand::run(const Json::Value &params, Json::Value &result) {
 
         check_param_count(params, m_param_count, result);
 
-        if (m_needs_ownership) {
+        if (m_needs_ownership && !g_test_override_ownership) {
             verify_ownership(params, result);
         }
 
@@ -372,3 +372,7 @@ TrexRpcCommand::generate_execute_err(Json::Value &result, const std::string &msg
     throw (TrexRpcCommandException(TREX_RPC_CMD_EXECUTE_ERR));
 }
 
+/**
+ * by default this is off
+ */
+bool TrexRpcCommand::g_test_override_ownership = false;
diff --git a/src/rpc-server/trex_rpc_cmd_api.h b/src/rpc-server/trex_rpc_cmd_api.h
index 7cbdf4ff..675d2900 100644
--- a/src/rpc-server/trex_rpc_cmd_api.h
+++ b/src/rpc-server/trex_rpc_cmd_api.h
@@ -89,6 +89,16 @@ public:
         return m_name;
     }
 
+    /**
+     * on test we enable this override
+     * 
+     * 
+     * @param enable 
+     */
+    static void test_set_override_ownership(bool enable) {
+        g_test_override_ownership = enable;
+    }
+
     virtual ~TrexRpcCommand() {}
 
 protected:
@@ -241,6 +251,8 @@ protected:
     std::string   m_name;
     int           m_param_count;
     bool          m_needs_ownership;
+
+    static bool   g_test_override_ownership;
 };
 
 #endif /* __TREX_RPC_CMD_API_H__ */
diff --git a/src/rpc-server/trex_rpc_req_resp_server.cpp b/src/rpc-server/trex_rpc_req_resp_server.cpp
index eb7825ac..1e8e177d 100644
--- a/src/rpc-server/trex_rpc_req_resp_server.cpp
+++ b/src/rpc-server/trex_rpc_req_resp_server.cpp
@@ -36,7 +36,10 @@ limitations under the License.
  * 
  */
 TrexRpcServerReqRes::TrexRpcServerReqRes(const TrexRpcServerConfig &cfg, std::mutex *lock) : TrexRpcServerInterface(cfg, "req resp", lock) {
-    /* ZMQ is not thread safe - this should be outside */
+
+}
+
+void TrexRpcServerReqRes::_prepare() {
     m_context = zmq_ctx_new();
 }
 
@@ -123,15 +126,28 @@ TrexRpcServerReqRes::fetch_one_request(std::string &msg) {
  */
 void TrexRpcServerReqRes::_stop_rpc_thread() {
     /* by calling zmq_term we signal the blocked thread to exit */
-    zmq_term(m_context);
+    if (m_context) {
+        zmq_term(m_context);
+    }
 
 }
 
+
 /**
  * handles a request given to the server
  * respondes to the request
  */
 void TrexRpcServerReqRes::handle_request(const std::string &request) {
+    std::string response_str = process_request(request);
+    zmq_send(m_socket, response_str.c_str(), response_str.size(), 0);
+}
+
+/**
+ * main processing of the request
+ * 
+ */
+std::string TrexRpcServerReqRes::process_request(const std::string &request) {
+
     std::vector<TrexJsonRpcV2ParsedObject *> commands;
 
     Json::FastWriter writer;
@@ -175,8 +191,7 @@ void TrexRpcServerReqRes::handle_request(const std::string &request) {
     
     verbose_json("Server Replied:  ", response_str);
 
-    zmq_send(m_socket, response_str.c_str(), response_str.size(), 0);
-    
+    return response_str;
 }
 
 /**
@@ -198,3 +213,36 @@ TrexRpcServerReqRes::handle_server_error(const std::string &specific_err) {
 
     zmq_send(m_socket, response_str.c_str(), response_str.size(), 0);
 }
+
+
+
+std::string
+TrexRpcServerReqRes::test_inject_request(const std::string &req) {
+    return process_request(req);
+}
+
+
+/**
+ * MOCK req resp server
+ */
+TrexRpcServerReqResMock::TrexRpcServerReqResMock(const TrexRpcServerConfig &cfg) : TrexRpcServerReqRes(cfg) {
+}
+
+/**
+ * override start
+ * 
+ */
+void
+TrexRpcServerReqResMock::start() {
+
+}
+
+
+/**
+ * override stop
+ */
+void
+TrexRpcServerReqResMock::stop() {
+
+}
+
diff --git a/src/rpc-server/trex_rpc_req_resp_server.h b/src/rpc-server/trex_rpc_req_resp_server.h
index 2876206c..97efbe08 100644
--- a/src/rpc-server/trex_rpc_req_resp_server.h
+++ b/src/rpc-server/trex_rpc_req_resp_server.h
@@ -34,13 +34,19 @@ public:
 
     TrexRpcServerReqRes(const TrexRpcServerConfig &cfg, std::mutex *lock = NULL);
 
+    /* for test purposes - bypass the ZMQ and inject a message */
+    std::string test_inject_request(const std::string &req);
+
 protected:
+
+    void _prepare();
     void _rpc_thread_cb();
     void _stop_rpc_thread();
 
-private:
     bool fetch_one_request(std::string &msg);
     void handle_request(const std::string &request);
+    std::string process_request(const std::string &request);
+
     void handle_server_error(const std::string &specific_err);
 
     void               *m_context;
@@ -48,4 +54,22 @@ private:
 };
 
 
+/**
+ * a mock req resp server (for tests)
+ * 
+ * @author imarom (03-Jan-16)
+ */
+class TrexRpcServerReqResMock : public TrexRpcServerReqRes {
+
+public:
+    TrexRpcServerReqResMock(const TrexRpcServerConfig &cfg);
+
+    /* override the interface functions */
+    virtual void start();
+    virtual void stop();
+
+
+};
+
 #endif /* __TREX_RPC_REQ_RESP_API_H__ */
+
diff --git a/src/rpc-server/trex_rpc_server.cpp b/src/rpc-server/trex_rpc_server.cpp
index a14e6f97..1dfc4494 100644
--- a/src/rpc-server/trex_rpc_server.cpp
+++ b/src/rpc-server/trex_rpc_server.cpp
@@ -63,6 +63,9 @@ void TrexRpcServerInterface::start() {
 
     verbose_msg("Starting RPC Server");
 
+    /* prepare for run */
+    _prepare();
+
     m_thread = new std::thread(&TrexRpcServerInterface::_rpc_thread_cb, this);
     if (!m_thread) {
         throw TrexRpcException("unable to create RPC thread");
@@ -117,9 +120,18 @@ TrexRpcServer::TrexRpcServer(const TrexRpcServerConfig *req_resp_cfg,
                              const TrexRpcServerConfig *async_cfg,
                              std::mutex *lock) {
 
+    m_req_resp = NULL;
+
     /* add the request response server */
     if (req_resp_cfg) {
-        m_servers.push_back(new TrexRpcServerReqRes(*req_resp_cfg, lock));
+
+        if (req_resp_cfg->get_protocol() == TrexRpcServerConfig::RPC_PROT_MOCK) {
+            m_req_resp = new TrexRpcServerReqResMock(*req_resp_cfg);
+        } else {
+            m_req_resp = new TrexRpcServerReqRes(*req_resp_cfg, lock);
+        }
+
+        m_servers.push_back(m_req_resp);
     }
     
     /* add async publisher */
@@ -166,3 +178,12 @@ void TrexRpcServer::set_verbose(bool verbose) {
     }
 }
 
+
+std::string
+TrexRpcServer::test_inject_request(const std::string &req_str) {
+    if (m_req_resp) {
+        return m_req_resp->test_inject_request(req_str);
+    } else {
+        return "";
+    }
+}
diff --git a/src/rpc-server/trex_rpc_server_api.h b/src/rpc-server/trex_rpc_server_api.h
index ff876ac4..1ab5dce9 100644
--- a/src/rpc-server/trex_rpc_server_api.h
+++ b/src/rpc-server/trex_rpc_server_api.h
@@ -29,8 +29,10 @@ limitations under the License.
 #include <string>
 #include <stdexcept>
 #include <trex_rpc_exception_api.h>
+#include <json/json.h>
 
 class TrexRpcServerInterface;
+class TrexRpcServerReqRes;
 
 /**
  * defines a configuration of generic RPC server
@@ -41,18 +43,19 @@ class TrexRpcServerConfig {
 public:
 
     enum rpc_prot_e {
-        RPC_PROT_TCP
+        RPC_PROT_TCP,
+        RPC_PROT_MOCK
     };
 
     TrexRpcServerConfig(rpc_prot_e protocol, uint16_t port) : m_protocol(protocol), m_port(port) {
 
     }
 
-    uint16_t get_port() {
+    uint16_t get_port() const {
         return m_port;
     }
 
-    rpc_prot_e get_protocol() {
+    rpc_prot_e get_protocol() const {
         return m_protocol;
     }
 
@@ -76,13 +79,13 @@ public:
      * starts the server
      * 
      */
-    void start();
+    virtual void start();
 
     /**
      * stops the server
      * 
      */
-    void stop();
+    virtual void stop();
 
     /**
      * set verbose on or off
@@ -107,6 +110,7 @@ protected:
      * instances implement this
      * 
      */
+    virtual void _prepare()                         = 0;
     virtual void _rpc_thread_cb()                   = 0;
     virtual void _stop_rpc_thread()                 = 0;
 
@@ -169,12 +173,23 @@ public:
     }
 
 
+    /**
+     * allow injecting of a JSON and get a response
+     * 
+     * @author imarom (27-Dec-15)
+     * 
+     * @return std::string 
+     */
+    std::string test_inject_request(const std::string &request_str);
    
 
 private:
     static std::string generate_handler();
 
     std::vector<TrexRpcServerInterface *>   m_servers;
+    // an alias to the req resp server
+    TrexRpcServerReqRes                     *m_req_resp;
+
     bool                                    m_verbose;
     static const std::string                s_server_uptime;
 
diff --git a/src/sim/trex_sim.h b/src/sim/trex_sim.h
new file mode 100644
index 00000000..cc02fd75
--- /dev/null
+++ b/src/sim/trex_sim.h
@@ -0,0 +1,146 @@
+/*
+ Itay Marom
+ Cisco Systems, Inc.
+*/
+
+/*
+Copyright (c) 2015-2015 Cisco Systems, Inc.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+#ifndef __TREX_SIM_H__
+#define __TREX_SIM_H__
+
+#include <string>
+#include <os_time.h>
+#include <bp_sim.h>
+#include <json/json.h>
+
+int gtest_main(int argc, char **argv);
+
+class TrexStateless;
+class TrexPublisher;
+class DpToCpHandler;
+
+/**
+ * interface for a sim target
+ * 
+ */
+class SimInterface {
+public:
+
+    SimInterface() {
+
+        time_init();
+        CGlobalInfo::m_socket.Create(0);
+        CGlobalInfo::init_pools(1000);
+    }
+
+    virtual ~SimInterface() {
+
+        CMsgIns::Ins()->Free();
+        CGlobalInfo::free_pools();
+        CGlobalInfo::m_socket.Delete();
+    }
+
+
+};
+
+/**
+ * gtest target
+ * 
+ * @author imarom (28-Dec-15)
+ */
+class SimGtest : public SimInterface {
+public:
+
+    int run(int argc, char **argv) {
+        assert( CMsgIns::Ins()->Create(4) );
+        return gtest_main(argc, argv);
+    }
+};
+
+
+
+/**
+ * stateful target
+ * 
+ */
+class SimStateful : public SimInterface {
+
+public:
+    int run();
+};
+
+
+
+/**
+ * target for sim stateless
+ * 
+ * @author imarom (28-Dec-15)
+ */
+class SimStateless : public SimInterface {
+
+public:
+    static SimStateless& get_instance() {
+        static SimStateless instance;
+        return instance;
+    }
+
+    
+    int run(const std::string &json_filename,
+            const std::string &out_filename,
+            int port_count,
+            int dp_core_count,
+            int dp_core_index);
+
+    TrexStateless * get_stateless_obj() {
+        return m_trex_stateless;
+    }
+
+    void set_verbose(bool enable) {
+        m_verbose = enable;
+    }
+
+private:
+    SimStateless();
+    ~SimStateless();
+
+    void prepare_control_plane();
+    void prepare_dataplane();
+    void execute_json(const std::string &json_filename);
+
+    void run_dp(const std::string &out_filename);
+    void run_dp_core(int core_index, const std::string &out_filename);
+
+    void flush_dp_to_cp_messages_core(int core_index);
+
+    void validate_response(const Json::Value &resp);
+
+    bool is_verbose() {
+        return m_verbose;
+    }
+
+    TrexStateless   *m_trex_stateless;
+    DpToCpHandler   *m_dp_to_cp_handler;
+    TrexPublisher   *m_publisher;
+    CFlowGenList     m_fl;
+    CErfIFStl        m_erf_vif;
+    bool             m_verbose;
+
+    int              m_port_count;
+    int              m_dp_core_count;
+    int              m_dp_core_index;
+};
+
+#endif /* __TREX_SIM_H__ */
diff --git a/src/sim/trex_sim_stateful.cpp b/src/sim/trex_sim_stateful.cpp
new file mode 100644
index 00000000..88698cd1
--- /dev/null
+++ b/src/sim/trex_sim_stateful.cpp
@@ -0,0 +1,600 @@
+/*
+ Itay Marom
+ Cisco Systems, Inc.
+*/
+
+/*
+Copyright (c) 2015-2015 Cisco Systems, Inc.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+#include "trex_sim.h"
+
+static int cores = 1;
+
+#ifdef LINUX
+
+
+
+#include <pthread.h>
+
+struct per_thread_t {
+    pthread_t  tid;
+};
+
+#define MAX_THREADS 200
+static per_thread_t  tr_info[MAX_THREADS];
+
+
+//////////////
+
+struct test_t_info1 {
+    CPreviewMode *            preview_info;
+    CFlowGenListPerThread   * thread_info;
+    uint32_t                  thread_id;
+};
+
+void * thread_task(void *info){
+
+    test_t_info1 * obj =(test_t_info1 *)info;
+
+    CFlowGenListPerThread   * lpt=obj->thread_info;
+
+    printf("start thread %d \n",obj->thread_id);
+    //delay(obj->thread_id *3000);
+    printf("-->start thread %d \n",obj->thread_id);
+    if (1/*obj->thread_id ==3*/) {
+
+        char buf[100];
+        sprintf(buf,"my%d.erf",obj->thread_id);
+        lpt->start_generate_stateful(buf,*obj->preview_info);
+        lpt->m_node_gen.DumpHist(stdout);
+        printf("end thread %d \n",obj->thread_id);
+    }
+
+    return (NULL);
+}
+
+
+void test_load_list_of_cap_files_linux(CParserOption * op){
+
+    CFlowGenList fl;
+    //CNullIF erf_vif;
+    //CErfIF erf_vif;
+
+    fl.Create();
+
+    fl.load_from_yaml(op->cfg_file,cores);
+    fl.DumpPktSize();
+
+    
+    fl.generate_p_thread_info(cores);
+    CFlowGenListPerThread   * lpt;
+
+    /* set the ERF file */
+    //fl.set_vif_all(&erf_vif);
+
+    int i;
+    for (i=0; i<cores; i++) {
+        lpt=fl.m_threads_info[i];
+        test_t_info1 * obj = new test_t_info1();
+        obj->preview_info =&op->preview;
+        obj->thread_info  = fl.m_threads_info[i];
+        obj->thread_id    = i;
+        CNullIF * erf_vif = new CNullIF();
+        //CErfIF  * erf_vif = new CErfIF();
+
+        lpt->set_vif(erf_vif);
+
+        assert(pthread_create( &tr_info[i].tid, NULL, thread_task, obj)==0);
+    }
+
+    for (i=0; i<cores; i++) {
+        /* wait for all of them to stop */
+       assert(pthread_join((pthread_t)tr_info[i].tid,NULL )==0);
+    }
+
+    printf("compare files \n");
+    for (i=1; i<cores; i++) {
+
+        CErfCmp cmp;
+        char buf[100];
+        sprintf(buf,"my%d.erf",i);
+        char buf1[100];
+        sprintf(buf1,"my%d.erf",0);
+        if ( cmp.compare(std::string(buf),std::string(buf1)) != true ) {
+            printf(" ERROR cap file is not ex !! \n");
+            assert(0);
+        }
+        printf(" thread %d is ok \n",i);
+    }
+
+    fl.Delete();
+}
+
+
+#endif
+
+/*************************************************************/
+void test_load_list_of_cap_files(CParserOption * op){
+
+    CFlowGenList fl;
+    CNullIF erf_vif;
+
+    fl.Create();
+
+    #define NUM 1
+
+    fl.load_from_yaml(op->cfg_file,NUM);
+    fl.DumpPktSize();
+    
+    
+    fl.generate_p_thread_info(NUM);
+    CFlowGenListPerThread   * lpt;
+
+    /* set the ERF file */
+    //fl.set_vif_all(&erf_vif);
+
+    int i;
+    for (i=0; i<NUM; i++) {
+        lpt=fl.m_threads_info[i];
+        char buf[100];
+        sprintf(buf,"my%d.erf",i);
+        lpt->start_generate_stateful(buf,op->preview);
+        lpt->m_node_gen.DumpHist(stdout);
+    }
+    //sprintf(buf,"my%d.erf",7);
+    //lpt=fl.m_threads_info[7];
+
+    //fl.Dump(stdout);
+    fl.Delete();
+}
+
+int load_list_of_cap_files(CParserOption * op){
+    CFlowGenList fl;
+    fl.Create();
+    fl.load_from_yaml(op->cfg_file,1);
+    if ( op->preview.getVMode() >0 ) {
+        fl.DumpCsv(stdout);
+    }
+    uint32_t start=    os_get_time_msec();
+
+    CErfIF erf_vif;
+    //CNullIF erf_vif;
+
+    fl.generate_p_thread_info(1);
+    CFlowGenListPerThread   * lpt;
+    lpt=fl.m_threads_info[0];
+    lpt->set_vif(&erf_vif);
+
+    if ( (op->preview.getVMode() >1)  || op->preview.getFileWrite() ) {
+        lpt->start_generate_stateful(op->out_file,op->preview);
+    }
+
+    lpt->m_node_gen.DumpHist(stdout);
+
+    uint32_t stop=    os_get_time_msec();
+    printf(" d time = %ul %ul \n",stop-start,os_get_time_freq());
+    fl.Delete();
+    return (0);
+}
+
+
+int test_dns(){
+
+    time_init();
+    CGlobalInfo::init_pools(1000);
+
+    CParserOption po ;
+
+    //po.cfg_file = "cap2/dns.yaml";
+    //po.cfg_file = "cap2/sfr3.yaml";
+    po.cfg_file = "cap2/sfr.yaml";
+
+    po.preview.setVMode(0);
+    po.preview.setFileWrite(true);
+    #ifdef LINUX
+      test_load_list_of_cap_files_linux(&po);
+    #else
+      test_load_list_of_cap_files(&po);
+    #endif
+    return (0);
+}
+
+void test_pkt_mbuf(void);
+
+void test_compare_files(void);
+
+#if 0
+static int b=0;
+static int c=0;
+static int d=0;
+
+int test_instructions(){
+    int i;
+    for (i=0; i<100000;i++) {
+        b+=b+1;
+        c+=+b+c+1;
+        d+=+(b*2+1);
+    }
+    return (b+c+d);
+}
+
+#include <valgrind/callgrind.h>
+#endif
+
+
+void update_tcp_seq_num(CCapFileFlowInfo * obj,
+                        int pkt_id,
+                        int size_change){
+    CFlowPktInfo * pkt=obj->GetPacket(pkt_id);
+    if ( pkt->m_pkt_indication.m_desc.IsUdp() ){
+        /* nothing to do */
+        return;
+    }
+
+    bool o_init=pkt->m_pkt_indication.m_desc.IsInitSide();
+    TCPHeader * tcp ;
+    int s= (int)obj->Size();
+    int i;
+
+    for (i=pkt_id+1; i<s; i++) {
+
+        pkt=obj->GetPacket(i);
+        tcp=pkt->m_pkt_indication.l4.m_tcp;
+        bool init=pkt->m_pkt_indication.m_desc.IsInitSide();
+        if (init == o_init) {
+            /* same dir update the seq number */
+            tcp->setSeqNumber    (tcp->getSeqNumber    ()+size_change);
+
+        }else{
+            /* update the ack number */
+            tcp->setAckNumber    (tcp->getAckNumber    ()+size_change);
+        }
+    }
+}
+
+
+
+void change_pkt_len(CCapFileFlowInfo * obj,int pkt_id, int size ){
+    CFlowPktInfo * pkt=obj->GetPacket(pkt_id);
+
+    /* enlarge the packet size by 9 */
+
+    char * p=pkt->m_packet->append(size);
+    /* set it to 0xaa*/
+    memmove(p+size-4,p-4,4); /* CRCbytes */
+    memset(p-4,0x0a,size);
+
+    /* refresh the pointers */
+    pkt->m_pkt_indication.RefreshPointers();
+
+    IPHeader       * ipv4 = pkt->m_pkt_indication.l3.m_ipv4;
+    ipv4->updateTotalLength	(ipv4->getTotalLength()+size );
+
+    /* update seq numbers if needed */
+    update_tcp_seq_num(obj,pkt_id,size);
+}
+
+void dump_tcp_seq_num_(CCapFileFlowInfo * obj){
+    int s= (int)obj->Size();
+    int i;
+    uint32_t i_seq;
+    uint32_t r_seq;
+
+    CFlowPktInfo * pkt=obj->GetPacket(0);
+    TCPHeader * tcp = pkt->m_pkt_indication.l4.m_tcp;
+    i_seq=tcp->getSeqNumber    ();
+
+    pkt=obj->GetPacket(1);
+    tcp = pkt->m_pkt_indication.l4.m_tcp;
+    r_seq=tcp->getSeqNumber    ();
+
+    for (i=2; i<s; i++) {
+        uint32_t seq;
+        uint32_t ack;
+
+        pkt=obj->GetPacket(i);
+        tcp=pkt->m_pkt_indication.l4.m_tcp;
+        bool init=pkt->m_pkt_indication.m_desc.IsInitSide();
+        seq=tcp->getSeqNumber    ();
+        ack=tcp->getAckNumber    ();
+        if (init) {
+            seq=seq-i_seq;
+            ack=ack-r_seq;
+        }else{
+            seq=seq-r_seq;
+            ack=ack-i_seq;
+        }
+        printf(" %4d ",i);
+        if (!init) {
+            printf("                             ");
+        }
+        printf("  %s   seq: %4d   ack : %4d   \n",init?"I":"R",seq,ack);
+    }
+}
+
+
+int manipolate_capfile() {
+    time_init();
+    CGlobalInfo::init_pools(1000);
+
+    CCapFileFlowInfo flow_info;
+    flow_info.Create();
+
+    flow_info.load_cap_file("avl/delay_10_rtsp_0.pcap",0,0);
+
+    change_pkt_len(&flow_info,4-1 ,6);
+    change_pkt_len(&flow_info,5-1 ,6);
+    change_pkt_len(&flow_info,6-1 ,6+2);
+    change_pkt_len(&flow_info,7-1 ,4);
+    change_pkt_len(&flow_info,8-1 ,6+2);
+    change_pkt_len(&flow_info,9-1 ,4);
+    change_pkt_len(&flow_info,10-1,6);
+    change_pkt_len(&flow_info,13-1,6);
+    change_pkt_len(&flow_info,16-1,6);
+    change_pkt_len(&flow_info,19-1,6);
+
+    flow_info.save_to_erf("exp/c.pcap",1);
+    
+    return (1);
+}
+
+int manipolate_capfile_sip() {
+    time_init();
+    CGlobalInfo::init_pools(1000);
+
+    CCapFileFlowInfo flow_info;
+    flow_info.Create();
+
+    flow_info.load_cap_file("avl/delay_10_sip_0.pcap",0,0);
+
+    change_pkt_len(&flow_info,1-1 ,6+6);
+    change_pkt_len(&flow_info,2-1 ,6+6);
+
+    flow_info.save_to_erf("exp/delay_10_sip_0_fixed.pcap",1);
+    
+    return (1);
+}
+
+int manipolate_capfile_sip1() {
+    time_init();
+    CGlobalInfo::init_pools(1000);
+
+    CCapFileFlowInfo flow_info;
+    flow_info.Create();
+
+    flow_info.load_cap_file("avl/delay_sip_0.pcap",0,0);
+    flow_info.GetPacket(1);
+
+    change_pkt_len(&flow_info,1-1 ,6+6+10);
+
+    change_pkt_len(&flow_info,2-1 ,6+6+10);
+
+    flow_info.save_to_erf("exp/delay_sip_0_fixed_1.pcap",1);
+    
+    return (1);
+}
+
+
+class CMergeCapFileRec {
+public:
+
+    CCapFileFlowInfo m_cap;
+
+    int              m_index;
+    int              m_limit_number_of_packets; /* limit number of packets */
+    bool             m_stop; /* Do we have more packets */
+
+    double           m_offset; /* offset should be positive */
+    double           m_start_time;
+
+public:
+    bool Create(std::string cap_file,double offset);
+    void Delete();
+    void IncPacket();
+    bool GetCurPacket(double & time);
+    CPacketIndication *  GetUpdatedPacket();
+
+    void Dump(FILE *fd,int _id);
+};
+
+
+void CMergeCapFileRec::Dump(FILE *fd,int _id){
+    double time = 0.0;
+    bool stop=GetCurPacket(time);
+    fprintf (fd," id:%2d  stop : %d index:%4d  %3.4f \n",_id,stop?1:0,m_index,time);
+}
+
+
+CPacketIndication *  CMergeCapFileRec::GetUpdatedPacket(){
+    double t1;
+    assert(GetCurPacket(t1)==false);
+    CFlowPktInfo * pkt = m_cap.GetPacket(m_index);
+    pkt->m_pkt_indication.m_packet->set_new_time(t1);
+    return (&pkt->m_pkt_indication);
+}
+
+
+bool  CMergeCapFileRec::GetCurPacket(double & time){
+    if (m_stop) {
+        return(true);
+    }
+    CFlowPktInfo * pkt = m_cap.GetPacket(m_index);
+    time= (pkt->m_packet->get_time() -m_start_time + m_offset);
+    return (false);
+}
+
+void CMergeCapFileRec::IncPacket(){
+    m_index++;
+    if ( (m_limit_number_of_packets) && (m_index > m_limit_number_of_packets ) ) {
+        m_stop=true;
+        return;
+    }
+
+    if ( m_index == (int)m_cap.Size() ) {
+        m_stop=true;
+    }
+}
+
+void CMergeCapFileRec::Delete(){
+    m_cap.Delete();
+}
+
+bool CMergeCapFileRec::Create(std::string cap_file,
+                              double offset){
+   m_cap.Create();
+   m_cap.load_cap_file(cap_file,0,0);
+   CFlowPktInfo * pkt = m_cap.GetPacket(0);
+
+   m_index=0;
+   m_stop=false;
+   m_limit_number_of_packets =0;
+   m_start_time =     pkt->m_packet->get_time() ;
+   m_offset = offset;
+
+   return (true);
+}
+
+
+
+#define MERGE_CAP_FILES (2)
+
+class CMergeCapFile {
+public:
+    bool Create();
+    void Delete();
+    bool run_merge(std::string to_cap_file);
+private:
+    void append(int _cap_id);
+
+public:
+    CMergeCapFileRec m[MERGE_CAP_FILES];
+    CCapFileFlowInfo m_results;
+};
+
+bool CMergeCapFile::Create(){
+    m_results.Create();
+    return(true);
+}
+
+void CMergeCapFile::Delete(){
+    m_results.Delete();
+}
+
+void CMergeCapFile::append(int _cap_id){
+    CPacketIndication * lp=m[_cap_id].GetUpdatedPacket();
+    lp->m_packet->Dump(stdout,0);
+    m_results.Append(lp);
+}
+
+
+bool CMergeCapFile::run_merge(std::string to_cap_file){
+
+    int i=0;
+    int cnt=0;
+    while ( true ) {
+        int    min_index=0;
+        double min_time;
+
+        fprintf(stdout," --------------\n");
+        fprintf(stdout," pkt : %d \n",cnt);
+        for (i=0; i<MERGE_CAP_FILES; i++) {
+            m[i].Dump(stdout,i);
+        }
+        fprintf(stdout," --------------\n");
+
+        bool valid = false;
+        for (i=0; i<MERGE_CAP_FILES; i++) {
+            double t1;
+            if ( m[i].GetCurPacket(t1) == false ){
+                /* not in stop */
+                if (!valid) {
+                    min_time  = t1;
+                    min_index = i;
+                    valid=true;
+                }else{
+                    if (t1 < min_time) {
+                        min_time=t1;
+                        min_index = i;
+                    }
+                }
+
+            }
+        }
+
+        /* nothing to do */
+        if (valid==false) {
+            fprintf(stdout,"nothing to do \n");
+            break;
+        }
+
+        cnt++;
+        fprintf(stdout," choose id %d \n",min_index);
+        append(min_index);
+        m[min_index].IncPacket();
+    };
+
+    m_results.save_to_erf(to_cap_file,1);
+
+    return (true);
+}
+
+
+
+int merge_3_cap_files() {
+    time_init();
+    CGlobalInfo::init_pools(1000);
+
+    CMergeCapFile merger;
+    merger.Create();
+    merger.m[0].Create("exp/c.pcap",0.001);
+    merger.m[1].Create("avl/delay_10_rtp_160k_0.pcap",0.31);
+    merger.m[2].Create("avl/delay_10_rtp_160k_1.pcap",0.311);
+
+    //merger.m[1].Create("avl/delay_10_rtp_250k_0_0.pcap",0.31);
+    //merger.m[1].m_limit_number_of_packets =6;
+    //merger.m[2].Create("avl/delay_10_rtp_250k_1_0.pcap",0.311);
+    //merger.m[2].m_limit_number_of_packets =6;
+
+    merger.run_merge("exp/delay_10_rtp_160k_full.pcap");
+
+    return (0);
+}
+
+int merge_2_cap_files_sip() {
+    time_init();
+    CGlobalInfo::init_pools(1000);
+
+    CMergeCapFile merger;
+    merger.Create();
+    merger.m[0].Create("exp/delay_sip_0_fixed_1.pcap",0.001);
+    merger.m[1].Create("avl/delay_video_call_rtp_0.pcap",0.51);
+    //merger.m[1].m_limit_number_of_packets=7;
+
+    //merger.m[1].Create("avl/delay_10_rtp_250k_0_0.pcap",0.31);
+    //merger.m[1].m_limit_number_of_packets =6;
+    //merger.m[2].Create("avl/delay_10_rtp_250k_1_0.pcap",0.311);
+    //merger.m[2].m_limit_number_of_packets =6;
+
+    merger.run_merge("avl/delay_10_sip_video_call_full.pcap");
+
+    return (0);
+}
+
+int
+SimStateful::run() {
+    assert( CMsgIns::Ins()->Create(4) );
+    return load_list_of_cap_files(&CGlobalInfo::m_options);
+}
diff --git a/src/sim/trex_sim_stateless.cpp b/src/sim/trex_sim_stateless.cpp
new file mode 100644
index 00000000..2821644f
--- /dev/null
+++ b/src/sim/trex_sim_stateless.cpp
@@ -0,0 +1,318 @@
+/*
+ Itay Marom
+ Cisco Systems, Inc.
+*/
+
+/*
+Copyright (c) 2015-2015 Cisco Systems, Inc.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+#include "trex_sim.h"
+#include <trex_stateless.h>
+#include <trex_stateless_messaging.h>
+#include <trex_rpc_cmd_api.h>
+#include <json/json.h>
+#include <stdexcept>
+#include <sstream>
+
+using namespace std;
+
+TrexStateless * get_stateless_obj() {
+    return SimStateless::get_instance().get_stateless_obj();
+}
+
+
+class SimRunException : public std::runtime_error 
+{
+public:
+    SimRunException() : std::runtime_error("") {
+
+    }
+    SimRunException(const std::string &what) : std::runtime_error(what) {
+    }
+};
+
+/*************** hook for platform API **************/
+class SimPlatformApi : public TrexPlatformApi {
+public:
+    SimPlatformApi(int dp_core_count) {
+        m_dp_core_count = dp_core_count;
+    }
+
+    virtual uint8_t get_dp_core_count() const {
+        return m_dp_core_count;
+    }
+
+    virtual void get_global_stats(TrexPlatformGlobalStats &stats) const {
+    }
+    virtual void get_interface_info(uint8_t interface_id, std::string &driver_name, driver_speed_e &speed) const {
+    }
+    virtual void get_interface_stats(uint8_t interface_id, TrexPlatformInterfaceStats &stats) const {
+    }
+
+    virtual void port_id_to_cores(uint8_t port_id, std::vector<std::pair<uint8_t, uint8_t>> &cores_id_list) const {
+        for (int i = 0; i < m_dp_core_count; i++) {
+             cores_id_list.push_back(std::make_pair(i, 0));
+        }
+    }
+
+private:
+    int m_dp_core_count;
+};
+
+/**
+ * handler for DP to CP messages
+ * 
+ * @author imarom (19-Nov-15)
+ */
+class DpToCpHandler {
+public:
+    virtual void handle(TrexStatelessDpToCpMsgBase *msg) = 0;
+};
+
+/************************ 
+ * 
+ *  stateless sim object
+ *  
+************************/
+class SimPublisher : public TrexPublisher {
+public:
+
+    /* override create */
+    bool Create(uint16_t port, bool disable) {
+        return true;
+    }
+
+    void Delete() {
+
+    }
+
+    void publish_json(const std::string &s) {
+    }
+
+    virtual ~SimPublisher() {
+    }
+};
+
+/************************ 
+ * 
+ *  stateless sim object
+ *  
+************************/
+
+SimStateless::SimStateless() {
+    m_trex_stateless    = NULL;
+    m_publisher         = NULL;
+    m_dp_to_cp_handler  = NULL;
+    m_verbose           = false;
+    m_dp_core_count     = -1;
+    m_dp_core_index     = -1;
+    m_port_count        = -1;
+
+    /* override ownership checks */
+    TrexRpcCommand::test_set_override_ownership(true);
+}
+
+
+int
+SimStateless::run(const string &json_filename,
+                  const string &out_filename,
+                  int port_count,
+                  int dp_core_count,
+                  int dp_core_index) {
+
+    assert(dp_core_count > 0);
+    assert(dp_core_index >= 0);
+    assert(dp_core_index < dp_core_count);
+
+    m_dp_core_count = dp_core_count;
+    m_dp_core_index = dp_core_index;
+    m_port_count    = port_count;
+
+    prepare_dataplane();
+    prepare_control_plane();
+
+    try {
+        execute_json(json_filename);
+    } catch (const SimRunException &e) {
+        std::cout << "*** test failed ***\n\n" << e.what() << "\n";
+        return (-1);
+    }
+
+    run_dp(out_filename);
+
+    return 0;
+}
+
+
+SimStateless::~SimStateless() {
+    if (m_trex_stateless) {
+        delete m_trex_stateless;
+        m_trex_stateless = NULL;
+    }
+
+    if (m_publisher) {
+        delete m_publisher;
+        m_publisher = NULL;
+    }
+
+    m_fl.Delete();
+}
+
+/**
+ * prepare control plane for test
+ * 
+ * @author imarom (28-Dec-15)
+ */
+void
+SimStateless::prepare_control_plane() {
+    TrexStatelessCfg cfg;
+    
+    m_publisher = new SimPublisher();
+
+    TrexRpcServerConfig rpc_req_resp_cfg(TrexRpcServerConfig::RPC_PROT_MOCK, 0);
+
+    cfg.m_port_count         = m_port_count;
+    cfg.m_rpc_req_resp_cfg   = &rpc_req_resp_cfg;
+    cfg.m_rpc_async_cfg      = NULL;
+    cfg.m_rpc_server_verbose = false;
+    cfg.m_platform_api       = new SimPlatformApi(m_dp_core_count);
+    cfg.m_publisher          = m_publisher;
+
+    m_trex_stateless = new TrexStateless(cfg);
+
+    m_trex_stateless->launch_control_plane();
+
+    for (auto &port : m_trex_stateless->get_port_list()) {
+        port->acquire("test", 0, true);
+    }
+
+}
+
+
+/**
+ * prepare the data plane for test
+ * 
+ */
+void
+SimStateless::prepare_dataplane() {
+    
+    CGlobalInfo::m_options.m_expected_portd = m_port_count;
+
+    assert(CMsgIns::Ins()->Create(m_dp_core_count));
+    m_fl.Create();
+    m_fl.generate_p_thread_info(m_dp_core_count);
+
+    for (int i = 0; i < m_dp_core_count; i++) {
+        m_fl.m_threads_info[i]->set_vif(&m_erf_vif);
+    }
+}
+
+
+
+void
+SimStateless::execute_json(const std::string &json_filename) {
+
+    std::ifstream test(json_filename);
+    std::stringstream buffer;
+    buffer << test.rdbuf();
+
+    std::string rep = m_trex_stateless->get_rpc_server()->test_inject_request(buffer.str());
+
+    Json::Value root;
+    Json::Reader reader;
+    reader.parse(rep, root, false);
+
+    if (is_verbose()) {
+        std::cout << "server response: \n\n" << root << "\n\n";
+    }
+
+    validate_response(root);
+
+}
+
+void
+SimStateless::validate_response(const Json::Value &resp) {
+    std::stringstream ss;
+
+    if (resp.isArray()) {
+        for (const auto &single : resp) {
+            if (single["error"] != Json::nullValue) {
+                ss << "failed with:\n\n" << single["error"] << "\n\n";
+                throw SimRunException(ss.str());
+            }
+        }
+    } else {
+        if (resp["error"] != Json::nullValue) {
+            ss << "failed with:\n\n" << resp["error"] << "\n\n";
+            throw SimRunException(ss.str());
+        }
+    }
+  
+}
+
+
+void
+SimStateless::run_dp(const std::string &out_filename) {
+
+    for (int i = 0; i < m_dp_core_count; i++) {
+        if (i == m_dp_core_index) {
+            run_dp_core(i, out_filename);
+        } else {
+            run_dp_core(i, "/dev/null");
+        }
+    }
+
+    CFlowGenListPerThread *lpt = m_fl.m_threads_info[m_dp_core_index];
+  
+    std::cout << "\n";
+    std::cout << "ports:        " << m_port_count << "\n";
+    std::cout << "cores:        " << m_dp_core_count << "\n";
+    std::cout << "core index:   " << m_dp_core_index << "\n";
+    std::cout << "\nwritten " << lpt->m_node_gen.m_cnt << " packets " << "to '" << out_filename << "'\n\n";
+}
+
+void
+SimStateless::run_dp_core(int core_index, const std::string &out_filename) {
+
+    CFlowGenListPerThread *lpt = m_fl.m_threads_info[core_index];
+
+    lpt->start_stateless_simulation_file((std::string)out_filename, CGlobalInfo::m_options.preview);
+    lpt->start_stateless_daemon_simulation();
+
+    flush_dp_to_cp_messages_core(core_index);
+}
+
+
+void
+SimStateless::flush_dp_to_cp_messages_core(int core_index) {
+
+    CNodeRing *ring = CMsgIns::Ins()->getCpDp()->getRingDpToCp(core_index);
+
+    while ( true ) {
+        CGenNode * node = NULL;
+        if (ring->Dequeue(node) != 0) {
+            break;
+        }
+        assert(node);
+
+        TrexStatelessDpToCpMsgBase * msg = (TrexStatelessDpToCpMsgBase *)node;
+        if (m_dp_to_cp_handler) {
+            m_dp_to_cp_handler->handle(msg);
+        }
+
+        delete msg;
+    }
+}
diff --git a/src/stateless/cp/trex_stateless.h b/src/stateless/cp/trex_stateless.h
index 5c11be1e..59be9241 100644
--- a/src/stateless/cp/trex_stateless.h
+++ b/src/stateless/cp/trex_stateless.h
@@ -161,6 +161,10 @@ public:
         return m_ports;
     }
 
+    TrexRpcServer * get_rpc_server() {
+        return m_rpc_server;
+    }
+
 protected:
 
     /* no copy or assignment */
@@ -168,7 +172,7 @@ protected:
     void operator=(TrexStateless const&)     = delete;
 
     /* RPC server array */
-    TrexRpcServer        *m_rpc_server;
+    TrexRpcServer                        *m_rpc_server;
 
     /* ports */
     std::vector <TrexStatelessPort *>    m_ports;
diff --git a/src/stateless/dp/trex_stateless_dp_core.cpp b/src/stateless/dp/trex_stateless_dp_core.cpp
index c211b9f5..0a9a88ab 100644
--- a/src/stateless/dp/trex_stateless_dp_core.cpp
+++ b/src/stateless/dp/trex_stateless_dp_core.cpp
@@ -353,8 +353,11 @@ void
 TrexStatelessDpCore::idle_state_loop() {
 
     while (m_state == STATE_IDLE) {
-        periodic_check_for_cp_messages();
-        delay(200);
+        bool had_msg = periodic_check_for_cp_messages();
+        /* if no message - backoff for some time */
+        if (!had_msg) {
+            delay(200);
+        }
     }
 }
 
diff --git a/src/stateless/dp/trex_stateless_dp_core.h b/src/stateless/dp/trex_stateless_dp_core.h
index 7dc4a2b2..efdb364c 100644
--- a/src/stateless/dp/trex_stateless_dp_core.h
+++ b/src/stateless/dp/trex_stateless_dp_core.h
@@ -185,12 +185,12 @@ public:
      * 
      * @author imarom (27-Oct-15)
      */
-    void periodic_check_for_cp_messages() {
+    bool periodic_check_for_cp_messages() {
         // doing this inline for performance reasons
 
         /* fast path */
         if ( likely ( m_ring_from_cp->isEmpty() ) ) {
-            return;
+            return false;
         }
 
         while ( true ) {
@@ -204,6 +204,8 @@ public:
             handle_cp_msg(msg);
         }
 
+        return true;
+
     }
 
     /* quit the main loop, work in both stateless in stateful, don't free memory trigger from  master  */