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From: Konstantin Ryabitsev <konstantin@linuxfoundation.org>
To: Eric Wong <e@80x24.org>
Cc: meta@public-inbox.org
Subject: Re: httpd 502s [was: trying to figure out 100% CPU usage in nntpd...]
Date: Wed, 11 Sep 2019 06:24:36 -0400	[thread overview]
Message-ID: <20190911102436.GA21959@pure.paranoia.local> (raw)
In-Reply-To: <20190911022215.GA309@dcvr>

On Wed, Sep 11, 2019 at 02:22:15AM +0000, Eric Wong wrote:
> Btw, some of the changes in public-inbox to use EPOLLET /
> EPOLLONESHOT would make it more sensitive to kernel bugs,
> and missed wakeups could cause resource exhaustion...
> 
> I just noticed this now:
> https://lore.kernel.org/lkml/20190904175303.918854334@linuxfoundation.org/
> 
> And I remember I found another mm-compaction-related issue
> several years back (early 3.x) which caused epoll wakeups to be
> missed...

To give some more data points, downgrading to f4f0a3be still shows a
number of /tmp/PerlIO* (deleted) entries, but the number of pipes stays
the same over time. If I switch to the latest master, the number of
broken pipes grows steadily following each git pull (in the hundreds
after 10 minutes of running).

I've downgraded lore.kernel.org to f4f0a3be for now to avoid the
resource exhaustion.

-K

  reply	other threads:[~2019-09-11 10:24 UTC|newest]

Thread overview: 21+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-09-08 10:45 [PATCH] nntp: regexp always consumes rbuf if "\n" exists Eric Wong
2019-09-08 10:52 ` trying to figure out 100% CPU usage in nntpd Eric Wong
2019-09-09 10:05   ` Konstantin Ryabitsev
2019-09-09 17:53     ` Eric Wong
2019-09-10  8:38       ` Konstantin Ryabitsev
2019-09-10 18:12         ` Eric Wong
2019-09-11  2:22           ` httpd 502s [was: trying to figure out 100% CPU usage in nntpd...] Eric Wong
2019-09-11 10:24             ` Konstantin Ryabitsev [this message]
2019-09-11 17:12               ` Eric Wong
2019-09-11 17:36                 ` Konstantin Ryabitsev
2019-09-12  0:05                   ` Eric Wong
2019-09-12  2:49                     ` Eric Wong
2019-09-12  8:35                       ` Eric Wong
2019-09-12 11:37                         ` Konstantin Ryabitsev
2019-09-13  3:12                           ` Eric Wong
2019-09-13  7:03                             ` Eric Wong
2019-09-13  9:01                             ` Eric Wong
2019-09-13 18:07                             ` Konstantin Ryabitsev
2019-09-14  5:25                               ` Eric Wong
2019-09-11  9:44           ` trying to figure out 100% CPU usage in nntpd Konstantin Ryabitsev
2019-09-11 17:12             ` Eric Wong

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