Hmm...I haven't tuned anything (this is just my workstation, not a server). /proc/sys/net/core/somaxconn 128 /proc/sys/net/ipv4/tcp_max_backlog doesn't exist
/proc/sys/net/ipv4/tcp_max_syn_backlog512 I guess those are pretty low for trying to thrash an echo server...any recommendations? On Thursday, 19 November 2015, 16:40, Willy Tarreau <w...@1wt.eu> wrote: Hi, On Thu, Nov 19, 2015 at 03:37:33AM +0000, Thrawn wrote: > OK, I've decided to go a bit easier on the stress tools ;), and limited > concurrency to 500, using siege. That's resulted in some useful data > (attached). > HAProxy HTTP endpoint, with 1 process, handled up to 500K total requests > without breaking a sweat, in just under 30 seconds, achieving an actual > concurrency of 160-170 (I'm guessing the requests finished too fast to go any > higher). For some reason, the longest request took almost all that time; > maybe that's again a limitation of the stress tool? Higher request volumes > introduced a small percentage of timeouts. Maybe you're hitting the accept backlog here. > Increasing to two HAProxy processes made a marked difference. At 500K > requests, total time halved to approximately 10-15 seconds. At higher > volumes, timeouts were much rarer; I was able to run 5 tests at 1.5M requests > each with no timeouts at all. Just for fun, I increased to 750 concurrency > (2.25M requests), with no trouble (the same test with 1 proc resulted in 57 > timeouts and about 30% longer run time). That also tends to confirm a backlog issue. What's your sys.net.core.somaxconn and sys.net.ipv4.tcp_max_backlog ? > PHP surprised me, actually; its performance characteristics were somewhat > better than HAProxy with 1 process (though I don't know how the memory usage > compared). However, compared to HAProxy with two processes, it had a somewhat > higher error rate and noticeably slower response time. > Looks like the conclusion is: use HAProxy, but tune nbproc wisely :) Normally at 500k in 30s (16k/s) you clearly don't need to use nbproc, so I'm pretty sure that you're hitting some network settings limits and your system needs to be tuned now. Willy