Could not fork: Not enough space



hello
I got this error in my syslog and my system is stoped responding. I am
not able to run any of the application. Than at last i have rebooted my
system and its working ok now. I just wanted to know why it was
happend. Can anyone help me

Apr 27 14:37:32 bkpmgmt prngd[1759]: Could not fork: Not enough space
Apr 27 14:57:08 bkpmgmt prngd[1759]: Could not fork: Not enough space
Apr 27 14:57:13 bkpmgmt above message repeats 17 times
Apr 27 14:57:59 bkpmgmt prngd[1759]: Could not fork: Not enough space
Apr 27 15:16:41 bkpmgmt prngd[1759]: Could not fork: Not enough space
Apr 27 15:17:13 bkpmgmt above message repeats 22 times
Apr 27 15:17:32 bkpmgmt prngd[1759]: Could not fork: Not enough space
Apr 27 15:29:28 bkpmgmt sshd[809]: error: fork: Not enough space
Apr 27 15:31:59 bkpmgmt prngd[1759]: Could not fork: Not enough space

Thanks in advance

Regards,
Parth

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