Justin Piszcz wrote: > Hello, > > Is it possible to 'optimize' ext4 so it is as fast as XFS for writes? > I see about half the performance as XFS for sequential writes. > > I have checked the doc and tried several options, a few of which are shown > below (I have also tried the commit/journal_async/etc options but none > of them get the write speeds anywhere near XFS)? > > Sure 'dd' is not a real benchmark, etc, etc, but with 10Gbps between 2 > hosts I get 550MiB/s+ on reads from EXT4 but only 100-200MiB/s write. > > When it was XFS I used to get 400-600MiB/s for writes for the same RAID > volume. > > How do I 'speed' up ext4? Is it possible? > FWIW I'm seeing similar things on fast storage (Fusion IO), though this is under 2.6.31. 500MB/s+ for xfs, 300 for ext4. Overwriting an existing file is no faster. I don't think this driver is blktraceable but I'll try a newer driver that should be I think. (xfs's overwrite went from 534 to 597 mb/s; ext4 sat at 320-ish) direct IO was good for both xfs & ext4 at around 530mb/s I'll see if I can get this running on a more recent kernel to do further investigation. -Eric -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
