trinity.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Jan Stancek <jstancek@redhat.com>
To: trinity@vger.kernel.org
Cc: jstancek@redhat.com, davej@codemonkey.org.uk
Subject: [bug] child processes stall forever and don't get killed
Date: Fri, 9 Sep 2016 06:30:16 -0400 (EDT)	[thread overview]
Message-ID: <210078090.1267922.1473417016250.JavaMail.zimbra@redhat.com> (raw)
In-Reply-To: <1139550397.1201862.1473415639192.JavaMail.zimbra@redhat.com>

Hi,

I'm running v1.6-643-gecea2b06d5f3 on RHEL7.3 and I'm seeing an issue
where all child processes stall and none of them is getting killed.
They are usually in a syscalls like read, recv, nanosleep, etc.

I suspect this commit introduced the problem, because any syscall
that started but not completed is now considered to "make progress":

  commit ecf6dfd83d4c886d78d4605163cb8c3f1728db62
  Author: Dave Jones <davej@codemonkey.org.uk>
  Date:   Fri Aug 12 15:05:01 2016 -0400

    if we haven't done a syscall yet, treat child as "making progress".
    
    Chances are that we haven't been scheduled because some other
    children are hogging the cpu.

I'm seeing more the opposite of what commit above says. Most CPUs
are idle, because N-1 children are stuck in recv/read/...
and last child manages to keep going. Then by a chance it also hits
a syscall that doesn't complete and system stays idle
(after ~hour I gave up waiting).

Regards,
Jan

       reply	other threads:[~2016-09-09 10:30 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <1139550397.1201862.1473415639192.JavaMail.zimbra@redhat.com>
2016-09-09 10:30 ` Jan Stancek [this message]
2016-09-09 13:32   ` [bug] child processes stall forever and don't get killed Dave Jones
2016-09-09 14:16     ` Jan Stancek
2016-09-10  1:46       ` Dave Jones
2016-09-13 12:00         ` Jan Stancek

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=210078090.1267922.1473417016250.JavaMail.zimbra@redhat.com \
    --to=jstancek@redhat.com \
    --cc=davej@codemonkey.org.uk \
    --cc=trinity@vger.kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).