Unstable local network throughput

[Ben RUBSON]

> On 17 Aug 2016, at 17:38, Adrian Chadd <adrian.chadd at gmail.com> wrote:
> 
> [snip]
> 
> ok, so this is what I was seeing when I was working on this stuff last.
> 
> The big abusers are:
> 
> * so_snd lock, for TX'ing producer/consumer socket data
> * tcp stack pcb locking (which rss tries to work around, but it again
> doesn't help producer/consumer locking, only multiple sockets)
> * for some of the workloads, the scheduler spinlocks are pretty
> heavily contended and that's likely worth digging into.
> 
> Thanks! I'll go try this on a couple of boxes I have with
> intel/chelsio 40g hardware in it and see if I can reproduce it. (My
> test boxes have the 40g NICs in NUMA domain 1...)

You're welcome, happy to help and troubleshoot :)

What about the performance which differs from one reboot to another,
as if the NUMA domains have switched ? (0 to 1 & 1 to 0)
Did you already see this ?

Ben