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diff --git a/docs/report/introduction/methodology_packet_latency.rst b/docs/report/introduction/methodology_packet_latency.rst deleted file mode 100644 index 35e2aad029..0000000000 --- a/docs/report/introduction/methodology_packet_latency.rst +++ /dev/null @@ -1,43 +0,0 @@ -.. _latency_methodology: - -Packet Latency --------------- - -TRex Traffic Generator (TG) is used for measuring one-way latency in -2-Node and 3-Node physical testbed topologies. TRex integrates `High -Dynamic Range Histogram (HDRH) <http://hdrhistogram.org/>`_ -functionality and reports per packet latency distribution for latency -streams sent in parallel to the main load packet streams. - -Following methodology is used: - -- Only NDRPDR test type measures latency and only after NDR and PDR - values are determined. Other test types do not involve latency - streams. -- Latency is measured at different background load packet rates: - - - No-Load: latency streams only. - - Low-Load: at 10% PDR. - - Mid-Load: at 50% PDR. - - High-Load: at 90% PDR. - -- Latency is measured for all tested packet sizes except IMIX due to - TRex TG restriction. -- TG sends dedicated latency streams, one per direction, each at the - rate of 9 kpps at the prescribed packet size; these are sent in - addition to the main load streams. -- TG reports Min/Avg/Max and HDRH latency values distribution per stream - direction, hence two sets of latency values are reported per test case - (marked as E-W and W-E). -- +/- 1 usec is the measurement accuracy of TRex TG and the data in HDRH - latency values distribution is rounded to microseconds. -- TRex TG introduces a (background) always-on Tx + Rx latency bias of 4 - usec on average per direction resulting from TRex software writing and - reading packet timestamps on CPU cores. Quoted values are based on TG - back-to-back latency measurements. -- Latency graphs are not smoothed, each latency value has its own - horizontal line across corresponding packet percentiles. -- Percentiles are shown on X-axis using a logarithmic scale, so the - maximal latency value (ending at 100% percentile) would be in - infinity. The graphs are cut at 99.9999% (hover information still - lists 100%).
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