[dpdk-dev] [RFC PATCH 0/4] testpmd: simulating noisy host environment

[Victor Kaplansky <vkaplans@redhat.com>]

This RFC patch propose enhancements to testpmd to simulate
more realistic behavior of a guest machine engaged in receiving
and sending packets performing Virtual Network Function (VNF).

The goal is to enable simple of measuring performance impact on cache and
memory footprint utilization from various VNF co-located on the
same host machine.

This series of patches adds the new command line switches to
testpmd:

--buffersize-before-sending [packet numbers]

    Keep the mbuf in a FIFO and forward the over flooding packets from the
    FIFO. This queue is per TX-queue (after all other packet processing).

--flush-timer [delay]
    Flush the packet queue if no packets have been seen during
    [delay]. As long as packets are seen, the timer is reset. 


Options to simulate route lookups:

--memory-footprint [size]
    Size of the VNF internal memory (MB), in which the random
    read/write will be done, allocated by rte_malloc (hugepages).

--random-w-memory-access-per-packet [num]
    Number of random writes in memory per packet should be
    performed, simulating hit-flags update. 64 bits per write,
    all write in different cache lines.

--random-r-memory-access-per-packet [num]
    Number of random reads in memory per packet should be
    performed, simulating FIB/table lookups.  64 bits per read,
    all write in different cache lines.

--random-rw-memory-access-per-packet [num]
    Number of random reads and writes in memory per packet should
    be performed, simulating stats update. 64 bits per read-write, all
    reads and writes in different cache lines.


Options to simulate packet processing (encap/decap)

--read-packet-buf [0-100]
    Determine the percentage of cache lines of a packet mbuf that
    testpmd should read for every packet.

--write-packet-buf [0-100]
    Determines the percentage of cache lines in the packet mbuf
    testpmd should write to.



Comments are welcomed. If name of command line switches seems
reasonable, I'll send rest of the patches with the implementation
in few days.

Regards,
-- 
Victor