.. _VPP_HDRH_Packet_Latency:
-HDRHistogram Packet Latency
-===========================
+Packet Latency
+==============
-.. todo::
- Introduction
+VPP latency results are generated based on the test data obtained from
+|csit-release| NDR-PDR throughput tests executed across physical
+testbeds hosted in LF FD.io labs: 3n-hsw, 3n-skx, 2n- skx, 2n-clx,
+3n-dnv, 2n-dnv, 3n-tsh.
+
+Latency by percentile distribution plots are used to show packet latency
+percentiles at different packet rate load levels: i) No-Load latency
+streams only, ii) Low-Load at 10% PDR, iii) Mid-Load at 50% PDR and iv)
+High-Load at 90% PDR.
+
+Additional information about graph data:
+
+#. **Graph Title**: describes tested DUT packet path.
+
+#. **X-axis Labels**: percentile of packets.
+
+#. **Y-axis Labels**: measured one-way packet latency values in [uSec].
+
+#. **Graph Legend**: list of latency tests at different packet rate load
+ level.
+
+#. **Hover Information**: packet rate load level, stream direction
+ (East-West, West-East), percentile, one-way latency.
.. note::
Test results have been generated by
- `FD.io test executor vpp performance job 2n-skx`_,
- `FD.io test executor vpp performance job 3n-skx`_,
- `FD.io test executor vpp performance job 2n-clx`_,
`FD.io test executor vpp performance job 3n-hsw`_ and
`FD.io test executor vpp performance job 3n-tsh`_ with RF
result files csit-vpp-perf-|srelease|-\*.zip