Re^3: Race condition in my cron daemon

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Re^4: Race condition in my cron daemon by clinton (Priest) on Apr 10, 2006 at 19:02 UTC
I couldn't get this DB lock working over the fork, so I've gone a different route: Fork Use Proc::PID::File to check that this job isn't running. If it is: Increment the number of attempts to start the job in the database Select the no of attempts from the DB - complain if greater than X Exit If it isn't running: Reset the no of attempts in the DB to zero Run the job This way I avoid locking the DB at all. Perrin, thanks for your help	[reply]
Re^5: Race condition in my cron daemon by perrin (Chancellor) on Apr 17, 2006 at 15:17 UTC
Glad to hear you found something that works. Sorry I couldn't spot the problem in the original code.	[reply]
Re^4: Race condition in my cron daemon by clinton (Priest) on Mar 27, 2006 at 10:04 UTC
Nope - still getting the same issue. I have added these lines to the code for the child process: `# Child # Get rid of old database connections > $lock->{InactiveDestroy} = 1; > undef $lock; > undef $db; MyStuff::DB::clear_cache(); chdir '/' or die $!;` [download] I still get the same issue where the parent locks the 'jobs' table, then when it tries to use the same dbh to write the new PID, it hangs, waiting for the lock. This only happens sporadically, and only when the child process has something to do (so that it takes fractionally longer to complete than usual), but not always... Further help would be greatly appreciated... clint	[reply] [d/l]