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ilovejedd · 09-28-2011, 02:01 AM

Yeah, weird title for this section but just wanted to comment how awesome SSDs are for large conversion jobs. I have a PHP script (max execution time=10 mins) that calls ebook-convert command-line and it kept timing out on a 50 chapter, 4MB HTML file. I wasn't getting any time-out errors when I first converted it 3 days ago (with a 5 minute time limit, even) so I was scratching my head on why I'm suddenly getting this issue. I forgot I was running the virtual disk from a mechanical drive since I ran out of space on the virtual machines SSD. Made space on my primary SSD so I could move the virtual machine to it and the conversion finished without a hitch and with plenty of time to spare.

The file was actually part of a 2,798 HTML -> ePub batch conversion queue. First run was on an Intel X25-V 40GB SSD and the whole job took less than 5 hours to complete (queued it at midnight and the job was finished when I woke up at 5AM). Made some changes to the PHP script (nothing that would greatly affect conversion to ePub) so I re-ran the script, this time on a Seagate Barracuda LP 2TB and there were still 500 or so files not converted after running for 6.5 hours. I reckon I'd be running the conversion again, this time on an Intel X25-M 120GB. It'll be interesting to see if there will be any difference in performance between the X25-M 120GB and the X25-V 40GB.

In any case, for folks working with large libraries, do yourself a favor and use an SSD for your Calibre library. Even an inexpensive 40~60GB SSD does wonders. Here I was thinking maybe Calibre might require a faster CPU or more cores when really, disk throughput and increased I/O apparently makes a more noticeable performance improvement.

09-28-2011, 02:01 AM	#1
ilovejedd hopeless n00b Posts: 5,110 Karma: 19597086 Join Date: Jan 2009 Location: in the middle of nowhere Device: PW4, PW3, Libra H2O, iPad 10.5, iPad 11, iPad 12.9	SSDs are great Yeah, weird title for this section but just wanted to comment how awesome SSDs are for large conversion jobs. I have a PHP script (max execution time=10 mins) that calls ebook-convert command-line and it kept timing out on a 50 chapter, 4MB HTML file. I wasn't getting any time-out errors when I first converted it 3 days ago (with a 5 minute time limit, even) so I was scratching my head on why I'm suddenly getting this issue. I forgot I was running the virtual disk from a mechanical drive since I ran out of space on the virtual machines SSD. Made space on my primary SSD so I could move the virtual machine to it and the conversion finished without a hitch and with plenty of time to spare. The file was actually part of a 2,798 HTML -> ePub batch conversion queue. First run was on an Intel X25-V 40GB SSD and the whole job took less than 5 hours to complete (queued it at midnight and the job was finished when I woke up at 5AM). Made some changes to the PHP script (nothing that would greatly affect conversion to ePub) so I re-ran the script, this time on a Seagate Barracuda LP 2TB and there were still 500 or so files not converted after running for 6.5 hours. I reckon I'd be running the conversion again, this time on an Intel X25-M 120GB. It'll be interesting to see if there will be any difference in performance between the X25-M 120GB and the X25-V 40GB. In any case, for folks working with large libraries, do yourself a favor and use an SSD for your Calibre library. Even an inexpensive 40~60GB SSD does wonders. Here I was thinking maybe Calibre might require a faster CPU or more cores when really, disk throughput and increased I/O apparently makes a more noticeable performance improvement.