The main part of the program (that serves an actual request) has 'issues'.

It's a web-based frontend to a DBM database. Thus, concurrent write access demands a single process locks the DBM file, and gives up it's lock after.

While the locking is working, performance of the software for multiple users is many many times worse than one would expect, given performance when there is no contention is excellent.

I suspect there may be some sort of lock thrashing or similar. I need to profile this main part of the program to determine what's going on.

The profilers I've seen all want to write to a single file, which is useless for the forked program, since it will be stomped by subsequent invocations.

In reply to Re: Re: Profiling a forking program by Tardis
in thread Profiling a forking program by Tardis

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