Are the boxes under quite a lot of load? Does this load vary during the day and does the occurence of the problem relate to this in any way?

You mention that the scripts are spawning children. Are they waiting for them to exit or running in parallel with them? How about the child scripts? Does task manager show a shedload of child processes running?

If you can't capture the problem at the time, turn on performance monitoring and graph these things over the day, so you can look for spikes/ceilings around the time of the problem. Also, don't just look at the bad machines, duplicate all the measurements on the 'good' ones and look for differences.

Do the machines tend to get sick at approx the same time (suggests an external, i.e. network factor)? Look at the network topology, do the sick machines share any factors there (same switch?)?

Some possibilities: 'memory' (vm exhaustion?), number of handles per process, maximum process stack depth (not perl stack, the underlying C stack), number of threads per proc, total number of procs running on the box, total number of threads on the box, etc.

Since its intermittent, it could be a more classic race, caused by general slowdown etc. So, lastly, can you 'induce' an episode by adding some load to one of your machines? Try different types of load (a cpu burner, a mem hog, a ping flood, a process which starts a lot of children).

It sounds like a build environment, so I wouldn't imagine the perl is too complex - is this right? Or is there a lot of hairy code in there? And again, what about the child processes?

Hope this helps, intermittent probs are always tough.

Good luck.

In reply to Re: Win32 - Memory can not be "read" by jbert
in thread Win32 - Memory can not be "read" by HuckinFappy

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