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Old 02-16-2011, 12:27 AM   #1
comox
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comox began at the beginning.
 
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0.7.45 (and earlier versions) conversion crash

0.7.45 on WinXP dual core system

I am attempting to batch convert about 6000 epubs to mobi using default conversion options.

I get a crash about once in every 20-50 books. It is not a new problem. I have observed this problem on several Calibre versions over the last 8 weeks.

If I leave the option "Maximum number of waiting worker process" at the default 6 then the crash causes Calibre (and all jobs) to terminate (and occasionally blue screen's XP). If I reduce this option to 2, then the active job crashes with an error but Calibre continues to operate and starts the next job.

I have a hunch that the cause of the problem is a memory leak. The time required to convert an epub to mobi can vary from a minute to several hours. I observe with Windows Task Manager that memory usage by calibre-parallel.exe increases constantly while the thread is running. For example, it starts at about 60 MB and 40 minutes later is consuming 300 MB. My hunch is that epubs with exceptionally long conversion times exceed some memory limit in Windows and crash. For example, I see that a job that was 107 minutes into a conversion eventually crashed.

I can provide logs and sample epubs on request but I suspect this will be very easy to reproduce. Just find an epub that is slow to convert and watch what happens with Windows Task Manager.

Thanks for an amazing product!
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