Why does my script exit with "Killed"

isync has asked for the wisdom of the Perl Monks concerning the following question:

Replies are listed 'Best First'.
Re: Why does my script exit with "Killed" - that's all... by jettero (Monsignor) on Jul 20, 2007 at 10:25 UTC
... it means that something killed it. I'm assuming a unixy platform here, which means there's no way to catch the SIGKILL, but you may find something in the /var/log files. That is, unless you generate an error somewhere like that in the program. -Paul	[reply]
Re: Why does my script exit with "Killed" - that's all... by Mutant (Priest) on Jul 20, 2007 at 10:35 UTC
It's probably something in the OS doing it, not within your script. If you're running Linux with a 2.4 or higher kernel, it will often be configured to kill off processes automatically if they reach a certain level of CPU or memory usage. Another possibility is ulimit (altho I'm not sure if that kills processes or just limits them).	[reply]
Re^2: Why does my script exit with "Killed" - that's all... by isync (Hermit) on Jul 20, 2007 at 11:04 UTC
I found it!! Something in the OS - that was also my first thought, as I did not write such a silly error msg into my script. I am running Debian/Linux (Ubuntu). And the hint to var log was right: I found in var/log/kern.log an entry which sais "Out of memory: Killed process 2832 (perl)", which is what triggered the event! What my server-script does: it consumes (and needs) quite an amount of memory (about 200MB of 1Gig system dram total). The log also tells some swapping happened before the event, I think that swap, plus system plus my script was just too much... Now, I will insert some tweaks to reduce ram usage, until the system receives more physical ram. Thanks again! (although I am not yet such an ace to know what oom and ulimit exactly is..;) )	[reply]
Re^3: Why does my script exit with "Killed" - that's all... by Mutant (Priest) on Jul 20, 2007 at 11:49 UTC
One thing you might want to try is restarting your server periodically (if that's practical). perl has a habit of accumulating memory over long periods of time. Restarting the process should reset all that.	[reply]
Re^3: Why does my script exit with "Killed" - that's all... by samizdat (Vicar) on Jul 20, 2007 at 13:42 UTC
Out Of Memory and User\|\|Usage (depending on which flavor) Limit :D Don Wilde "There's more than one level to any answer."	[reply]
Re^2: Why does my script exit with "Killed" - that's all... by jettero (Monsignor) on Jul 20, 2007 at 10:56 UTC
In linux, the OOM killer kills. I suspect the ulimit memory killer does too... It probably changes from nix to nix though. I wonder if the oom killer is the ulimit killer. Huh. -Paul	[reply]
Re: Why does my script exit with "Killed" - that's all... by Anonymous Monk on Jul 20, 2007 at 11:43 UTC
Is there a way to measure the size of my data structures while the script is running? If so, I could test my structures for size every few cycles and see if there is a memory leak I didn't thought of.	[reply]
Re^2: Why does my script exit with "Killed" - that's all... by dsheroh (Monsignor) on Jul 20, 2007 at 14:12 UTC
I typically watch this by running `top` and keeping an eye on the `VIRT` (total memory usage) and/or `RES` (physical/non-swap memory usage) columns.	[reply] [d/l] [select]