Justin Piszcz <jpiszcz@xxxxxxxxxxxxxxx> writes: > 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? I don't know how to speedup, but i do know how to slowdown XFS :) Seems that you forget to call fsync at the end of file write In this case some data may reside in memory cache. Please add "conv=fsync" or "conv=fdatasync" to the dd cmd. And redone your measurements. > > raid0_11 disks: (XFS) > # /dev/md0 /r1 xfs noatime 0 1 > p63:/r1# dd if=/dev/zero of=bigfile1 bs=1M count=10240 > 10240+0 records in > 10240+0 records out > 10737418240 bytes (11 GB) copied, 18.1021 s, 593 MB/s > p63:/r1# > > raid0_11 disks: (EXT4) > # /dev/md0 /r1 ext4 noatime 0 1 > # dd if=/dev/zero of=file bs=1M count=10240 > 10240+0 records in > 10240+0 records out > 10737418240 bytes (11 GB) copied, 35.3741 s, 304 MB/s > p63:/r1# > > Other tests (ext4) > p63:~# mount /dev/md0 /r1 -o data=writeback > p63:~# cd /r1 > p63:/r1# dd if=/dev/zero of=file bs=1M count=10240 > 10240+0 records in > 10240+0 records out > 10737418240 bytes (11 GB) copied, 39.8746 s, 269 MB/s > p63:/r1# > > p63:~# mount /dev/md0 /r1 -o data=writeback,nobarrier > p63:/r1# dd if=/dev/zero of=file bs=1M count=10240 > 10240+0 records in > 10240+0 records out > 10737418240 bytes (11 GB) copied, 40.0656 s, 268 MB/s > > Justin. > -- > 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 -- 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
