2008/10/11 Anthony wikimail@inbox.org:
On Sat, Oct 11, 2008 at 9:39 AM, Thomas Dalton thomas.dalton@gmail.comwrote:
If you want to add two more threads you would need to add more servers to run them. I can't see why they would be I/O bound, they aren't writing anything to the database so can just use slave database servers of which there are plenty.
My understanding is that the processes have to read from the stub dumps and and write to the history dumps. In my experience, though admittedly with cheap hard drives and an untweaked linux system running ext3, running two such processes (accessing 4 files on the same hard drive) on a dual-CPU system is I/O bound (presumably due to the disk seeks, since you can hear the difference on the poor hard drive). I'm sure some tweaks could be made to solve this, but I haven't figured them out yet (at least, not other than the obvious one of using 2 or even 4 hard drives which I just can't afford).
Hard drives are pretty cheap, installing a second drive to take better advantage of a dual-CPU system wouldn't be too difficult.