On Fri, Aug 09, 2013 at 11:35:33PM +0200, Kai Krakow wrote: > Josef Bacik <jbacik@xxxxxxxxxxxx> schrieb: > > >> So I guess the reason that ZFS does well with that workload is that > >> ZFS is using smaller blocks, maybe just 512B ? > > > > Yeah I'm not sure what ZFS does, but if you are writing over a block and > > the size/offset isn't aligned then you'd see similar issues with ZFS since > > it would > > have to read+modify+write. It is likely that ZFS just is using a smaller > > blocksize. > > From what I remember, ZFS uses dynamic block sizes. However, block size can > be forced and thus tuned for workloads that require it: > > http://www.joyent.com/blog/bruning-questions-zfs-record-size > > Maybe that's the reason... > > It would be interesting to see how the benchmarks performed with forced > block size. > When I did bs=4k in the fio job to force it to use 4k blocksizes we performed the same as ext4 and xfs. Thanks, Josef -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
