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diff --git a/docs/development/design/ndrpdr.rst b/docs/development/design/ndrpdr.rst deleted file mode 100644 index 5361174..0000000 --- a/docs/development/design/ndrpdr.rst +++ /dev/null @@ -1,44 +0,0 @@ -.. This work is licensed under a Creative Commons Attribution 4.0 International -.. License. -.. http://creativecommons.org/licenses/by/4.0 -.. (c) Cisco Systems, Inc - -NDR/PDR Binary Search -===================== - -Algorithm Outline ------------------ - -The ServiceChain class is responsible for calculating the NDR/PDR for all frame sizes requested in the configuration. -Calculation for 1 frame size is delegated to the TrafficClient class. - -Call chain for calculating the NDR-PDR for a list of frame sizes: - -- ServiceChain.run() - - ServiceChain._get_chain_results() - - for every frame size: - - ServiceChain.__get_result_per_frame_size() - - TrafficClient.get_ndr_pdr() - - TrafficClient.__range_search() recursive binary search - -The search range is delimited by a left and right rate (expressed as a % of line rate per direction). - -The load_epsilon configuration parameter defines the accuracy of the result as a % of line rate. -The default value of 0.1 indicates for example that the measured NDR and PDR are within 0.1% of line rate of the -actual NDR/PDR (e.g. 0.1% of 10Gbps is 10Mbps). It also determines how small the search range must be in the binary search. - -The recursion narrows down the range by half and stops when: - -- the range is smaller than the configured load_epsilon value -- or when the search hits 100% or 0% of line rate - -One particularity of using a software traffic generator is that the requested Tx rate may not always be met due to -resource limitations (e.g. CPU is not fast enough to generate a very high load). The algorithm should take this into -consideration: - -- always monitor the actual Tx rate achieved -- actual Tx rate is always <= requested Tx rate -- the measured drop rate should always be relative to the actual Tx rate -- if the actual Tx rate is < requested Tx rate and the measured drop rate is already within threshold (<NDR/PDR threshold) then the binary search must stop with proper warning - - |