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From: erik quanstrom <quanstro@quanstro.net>
To: 9fans@9fans.net
Subject: Re: [9fans] file descriptor leak
Date: Sun, 21 Feb 2016 21:18:26 -0800	[thread overview]
Message-ID: <ac9553f128c3ec07e9dc50de0080361d@mule> (raw)
In-Reply-To: <CAOw7k5jCGQCcivH6nonTC=u8FpN0XQ4YQOerM1TXQTFjogW_Zg@mail.gmail.com>

On Tue Feb 16 13:19:29 PST 2016, charles.forsyth@gmail.com wrote:

> On 16 February 2016 at 18:01, <cinap_lenrek@felloff.net> wrote:
>
> > and the parent proc doesnt need the fd to /dev/null, it could as well just
> > open it in the child like:
> >
> > close(0); open("/dev/null", OREAD);
> >
> >
> There's no harm in making and using a more general function, even in a
> specific way, so that part's ok.
> The caller just needs to play its part properly.
>
> after spending 5 minutes writing the code fixing all these issues mentiond
> > above, i'll just throw it all away and delete the whole remounting logic
> > for /net.alt in 9front.
>
>
> It's often better to use the Erlang fail-fast ("just fail") and restart
> approach for persistent services.
>
> More important would be to look at /proc/N/fd on a failing system.
> I've a feeling that the system/outside stuff isn't actually the problem,
> since I've seen the diagnostic on a system that wasn't using /net.alt.
> In that case, the problem (as I remember it) was that an Internet link
> further on was down,
> so no messages got through to remote DNS, and file descriptors were
> building up in slave processes
> waiting for replies on /net/udp. Once the link was up, it went back to
> normal.

we saw this a lot at coraid, but never did catch a smoking-gun process.
i don't recall a perfect correlation to internet down.

- erik



  parent reply	other threads:[~2016-02-22  5:18 UTC|newest]

Thread overview: 13+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-02-16 15:52 arisawa
2016-02-16 15:56 ` Jacob Todd
2016-02-16 16:42   ` lucio
2016-02-16 17:05     ` Jacob Todd
2016-02-16 17:17     ` Charles Forsyth
2016-02-16 18:01 ` cinap_lenrek
2016-02-16 21:05   ` erik quanstrom
2016-02-16 21:16   ` Charles Forsyth
2016-02-17  2:19     ` cinap_lenrek
2016-02-22  5:18     ` erik quanstrom [this message]
2016-02-16 22:24 ` Charles Forsyth
2016-02-17  1:13   ` arisawa
2016-02-17  1:22     ` cinap_lenrek

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