in reply to Backticks with Apache hang

I had the same problem few weeks ago.

I've managed to isolate the problem to a weird interraction between Apache::Session via a NFS share and the offending code. Whenever I called the code that used the Session, any execution resulting in a fork (backtick, pipe, watever) would end with a hanged Apache child and a frozen process.

What was weird is that the problem occured systematically with RedHat EL4, but not on the boxes running RHEL3...

The problem disapeared when we moved the session management to MySQL.

Try to strace the processed? When I did, it at least helped be figure the interraction of everything (it was not my code).

Hope this help, good luck.

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Re^2: Backticks with Apache hang
by Marcello (Hermit) on Oct 14, 2005 at 10:34 UTC
    strace revealed the following: 
    fork()                                  = -1 EAGAIN (Resource temporar
+ily unavailable)
rt_sigprocmask(SIG_BLOCK, [CHLD], [RT_0], 8) = 0
rt_sigaction(SIGCHLD, NULL, {SIG_DFL}, 8) = 0
rt_sigprocmask(SIG_SETMASK, [RT_0], NULL, 8) = 0
nanosleep({5, 0}, {5, 0})               = 0

    [download]
    Which is really strange, what might cause the fork to fail for Apache requests?
[reply]
[d/l]

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