On Sat, Jun 04, 2011 at 03:14:53AM -0500, Stan Hoeppner wrote: > On 6/3/2011 10:59 AM, Paul Anderson wrote: > > Not sure what I can do about the log - man page says xfs_growfs > > doesn't implement log moving. I can rebuild the filesystems, but for > > the one mentioned in this theread, this will take a long time. > > See the logdev mount option. Using two mirrored drives was recommended, > I'd go a step further and use two quality "consumer grade", i.e. MLC > based, SSDs, such as: > > http://www.cdw.com/shop/products/Corsair-Force-Series-F40-solid-state-drive-40-GB-SATA-300/2181114.aspx > > Rated at 50K 4K write IOPS, about 150 times greater than a 15K SAS drive. If you are using delayed logging, then a pair of mirrored 7200rpm SAS or SATA drives would be sufficient for most workloads as the log bandwidth rarely gets above 50MB/s in normal operation. If you have fsync heavy workloads, or are not using delayed logging, then you really need to use the RAID5/6 device behind a BBWC because the log is -seriously- bandwidth intensive. I can drive >500MB/s of log throughput on metadata intensive workloads on 2.6.39 when not using delayed logging or I'm regularly forcing the log via fsync. You sure as hell don't want to be running a sustained long term write load like that on consumer grade SSDs..... Cheers, Dave. -- Dave Chinner david@xxxxxxxxxxxxx _______________________________________________ xfs mailing list xfs@xxxxxxxxxxx http://oss.sgi.com/mailman/listinfo/xfs
