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Hi all

When running multiple HTTP requests via LWP, I occasionally get this error: select failed: no child processes. If I catch the error, and wait a little, I can repeat the request successfully.

The code from LWP::Protocol::http which throws this error is this:

    269        SELECT:
    270             {
    271                 my $nfound = select($rbits, $wbits, undef, $se
+l_timeout);
    272                 if ($nfound < 0) {
    273                     if ($!{EINTR} || $!{EAGAIN}) {
    274                         if ($time_before) {
    275                             $sel_timeout = $sel_timeout_before
+ - (time - $time_before);
    276                             $sel_timeout = 0 if $sel_timeout <
+ 0;
    277                         }
    278                         redo SELECT;
    279                     }
    280                     die "select failed: $!";
    281                 }
    282         }
[download]

It seems I am running into some system limit, but I can't figure out which. ulimit -a on this (linux) system outputs this:

    core file size          (blocks, -c) 0
    data seg size           (kbytes, -d) unlimited
    scheduling priority             (-e) 0
    file size               (blocks, -f) unlimited
    pending signals                 (-i) 27968
    max locked memory       (kbytes, -l) 32
    max memory size         (kbytes, -m) unlimited
    open files                      (-n) 16384
    pipe size            (512 bytes, -p) 8
    POSIX message queues     (bytes, -q) 819200
    real-time priority              (-r) 0
    stack size              (kbytes, -s) 10240
    cpu time               (seconds, -t) unlimited
    max user processes              (-u) 27968
    virtual memory          (kbytes, -v) unlimited
    file locks                      (-x) unlimited
[download]

And the limits as reported by BSD::Resource are as follows:

    RLIMIT_CPU :        -1
    RLIMIT_OPEN_MAX :   16384
    RLIMIT_LOCKS :      -1
    RLIMIT_VMEM :       -1
    RLIMIT_FSIZE :      -1
    RLIMIT_STACK :      10485760
    RLIMIT_MEMLOCK :    32768
    RLIMIT_NOFILE :     16384
    RLIMIT_DATA :       -1
    RLIMIT_NPROC :      27968
    RLIMIT_OFILE :      16384
    RLIMIT_AS :         -1
    RLIMIT_CORE :       0
    RLIMIT_RSS :        -1
[download]

Any ideas what I can change to get around this?

thanks

Clint

In reply to No child processes - system limit? by clinton

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