(switched to email. Please respond via emailed reply-to-all, not via the bugzilla web interface). scsi_drivers-other reports don't appear to be coming out on the linux-scsi list. On Sat, 3 Apr 2010 21:16:31 GMT bugzilla-daemon@xxxxxxxxxxxxxxxxxxx wrote: > https://bugzilla.kernel.org/show_bug.cgi?id=15688 > > Summary: mptsas & poor performance > Product: SCSI Drivers > Version: 2.5 > Kernel Version: 2.6.34-020634rc1 > Platform: All > OS/Version: Linux > Tree: Mainline > Status: NEW > Severity: normal > Priority: P1 > Component: Other > AssignedTo: scsi_drivers-other@xxxxxxxxxxxxxxxxxxxx > ReportedBy: bexamous@xxxxxxxxx > Regression: No > > > The mptsas module from LSI's website, v4.18.00.00, performs much better than > the mptsas module included in the kernel, v3.something. > > I'm only comparing sequential writes (dd if=/dev/zero of=zeros bs=1M), but... > > 6 drive MD RAID5 with fresh btrfs, writing 10GB of zeros with dd, > kernel version: <200MB/sec > LSI's v4.18.00.00: 395MB/sec > > Pretty big difference. I've gone back and forth a few times, > enabling/disabling write cache on the drives, enabling/disabling ioc, > enabling/disabling filesystem barriers... I can make small changes in > performance but nothing compares to simply updating to v4.18.00.00. > -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html