594301 - When opening new tab (especially on bugzilla.mozilla.org) Firefox freezes for a moment in FUTEX_WAKE_PRIVATE / FUTEX_WAIT_BITSET_PRIVATE|FUTEX_CLOCK_REALTIME cycle

Status: NEW

(Firefox :: General, defect)

Description

[Matěj Cepl]

Attachment: output of strace -f -p $(/sbin/pidof firefox)

When browsing through some sites (especially pronounced it is on b.m.o) when I open a new tab (Ctrl-click usually) whole browser freezes for a moment. When attaching strace to firefox, I get number of lines like this

[pid 27812] futex(0x7f05d44fec0c, FUTEX_WAIT_PRIVATE, 30751, NULL <unfinished ...>
[pid 27811] restart_syscall(<... resuming interrupted call ...> <unfinished ...>
[pid 27810] restart_syscall(<... resuming interrupted call ...> <unfinished ...>
[pid 27809] futex(0x7f05d645644c, FUTEX_WAIT_PRIVATE, 741, NULL <unfinished ...>
[pid 27808] restart_syscall(<... resuming interrupted call ...> <unfinished ...>
[pid 27807] epoll_wait(14,  <unfinished ...>
[pid 27810] <... restart_syscall resumed> ) = -1 ETIMEDOUT (Connection timed out)
[pid 27810] futex(0x7f05d64575e0, FUTEX_WAKE_PRIVATE, 1) = 0
[pid 27810] futex(0x7f05d64565cc, FUTEX_WAIT_BITSET_PRIVATE|FUTEX_CLOCK_REALTIME, 17353, {1283937486, 481666000}, ffffffff) = -1 ETIMEDOUT (Connection timed out)
[pid 27810] futex(0x7f05d64575e0, FUTEX_WAKE_PRIVATE, 1) = 0
[pid 27810] futex(0x7f05d64565cc, FUTEX_WAIT_BITSET_PRIVATE|FUTEX_CLOCK_REALTIME, 17355, {1283937487, 481878000}, ffffffff) = -1 ETIMEDOUT (Connection timed out)
[pid 27810] futex(0x7f05d64575e0, FUTEX_WAKE_PRIVATE, 1) = 0
[pid 27810] futex(0x7f05d64565cc, FUTEX_WAIT_BITSET_PRIVATE|FUTEX_CLOCK_REALTIME, 17357, {1283937488, 482087000}, ffffffff <unfinished ...>
[pid 27811] <... restart_syscall resumed> ) = -1 ETIMEDOUT (Connection timed out)
[pid 27811] futex(0x7f05d7a1e950, FUTEX_WAKE_PRIVATE, 1) = 0
[pid 27811] futex(0x7f05d7a594cc, FUTEX_WAIT_BITSET_PRIVATE|FUTEX_CLOCK_REALTIME, 9100531, {1283937488, 379671000}, ffffffff) = -1 ETIMEDOUT (Connection timed out)

when these end in strace, browser unfreezes.

Comment 1

[Matěj Cepl]

I don't see bugzilla adding a version of my Firefox:

Mozilla/5.0 (X11; Linux x86_64; rv:2.0b4) Gecko/20100903 Fedora/4.0-0.6.b4.fc14 Firefox/4.0b4

(it is a Fedora package from unofficial Fedora repository on http://repos.fedorapeople.org/repos/spot/firefox4/)

Comment 2

[michael-dev]

Does running "sudo date `date +"%m%d%H%M%C%y.%S"`" help you?

http://serverfault.com/questions/407224/java-process-opends-consumes-all-cpu-futex-flood-how-to-
debug-futex