Messages in this thread |  | | | Date | Mon, 07 Mar 2005 01:22:31 -0800 | | From | Ben Greear <> | | Subject | Re: BUG: Slowdown on 3000 socket-machines tracked down |
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Nick Piggin wrote: > Ben Greear wrote: > >> Christian Schmid wrote: >> >>> Ben Greear wrote: > > >>>> How many bytes are you sending with each call to write()/sendto() >>>> whatever? >>> >>> >>> >>> I am using sendfile-call every 100 ms per socket with the poll-api. >>> So basically around 40 kb per round. >> >> >> >> My application is single-threaded, uses non-blocking IO, and >> sends/rcvs from/to memory. >> It will be a good test of the TCP stack, but will not use the sendfile >> logic, >> nor will it touch the HD. >> > > I think you would have better luck in reproducing this problem if you > did the full sendfile thing. > > I think it is becoming disk bound due to page reclaim problems, which > is causing the slowdown. > > In that case, writing the network only test would help to confirm the > problem is not a networking one - so not useless by any means.
It's not trivial to write something like this :)
I'll be using something I already have. If I can't reproduce the problem, then perhaps it is due to sendfile and someone can write a customized test. The main reason I offered is because people are ignoring the bug report for the most part and asking for a test case. I may be able to offer an independent verification of the problem which might convince someone to write up a dedicated test case...
Ben
-- Ben Greear <greearb@candelatech.com> Candela Technologies Inc http://www.candelatech.com
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