On Tue, Jan 31, 2012 at 09:52:10PM +0000, Brian Candler wrote: > On Tue, Jan 31, 2012 at 09:52:05AM -0500, Christoph Hellwig wrote: > > You don't just read a single file at a time but multiple ones, don't > > you? > > It's sequential at the moment, although I'll do further tests with the -c > (concurrency) option to bonnie++ > > > Try playing with the following tweaks to get larger I/O to the disk: > > > > a) make sure you use the noop or deadline elevators > > b) increase /sys/block/sdX/queue/max_sectors_kb from its low default > > c) dramatically increase /sys/devices/virtual/bdi/<major>:<minor>/read_ahead_kb > > Thank you very much: I will do further tests with these. > > Is the read_ahead_kb knob aware of file boundaries? That is, is there any > risk that if I set it too large it would read useless blocks past the end of > the file? Yes, readahead only occurs within the file, and won't readahead past EOF. Cheers, Dave. -- Dave Chinner david@xxxxxxxxxxxxx _______________________________________________ xfs mailing list xfs@xxxxxxxxxxx http://oss.sgi.com/mailman/listinfo/xfs
