Did anything change in the mpt fusion driver? I'm seeing the same thing, again with mpt-fusion. 38MB/sec when it should be getting >60.
Begin forwarded message: Date: Mon, 28 Feb 2005 22:03:57 -0800 From: [EMAIL PROTECTED] To: [EMAIL PROTECTED] Subject: [Bugme-new] [Bug 4268] New: SCSI performance regression in 2.6.10 http://bugme.osdl.org/show_bug.cgi?id=4268 Summary: SCSI performance regression in 2.6.10 Kernel Version: 2.6.10 Status: NEW Severity: normal Owner: [EMAIL PROTECTED] Submitter: [EMAIL PROTECTED] Distribution: Debian 'unstable', pristine 2.6.10 kernel Hardware Environment: HP rx2600 (ia64), LSI 53C1030 U320 SCSI host (Fusion MPT) Problem Description: There is a quite severe performance regression in 2.6.10 when using SCSI disk drives. (I've tested against 2.4.20, 2.6.8 and 2.6.9, none of which exhibit this problem) Steps to reproduce: dd if=/dev/sdXX of=/dev/null bs=1048576 count=10000 (streaming read the first 10GB of scsi disk XX) In 2.6.10, with a Fujitsu 10Krpm SCSI disk I get 34MB/sec, with a Maxtor 15Krpm SCSI disk I get 37MB/sec. CPU usage of 'dd' is ~2% and %system time is about the same. Using 2.6.9 (or earlier), I get 63MB/sec for the 10K disk and 95MB/sec for the 15K disk. CPU usage goes up in proportion. (OK, fair enough.) This is a real performance issue (shows up everywhere, not just in 'dd'), and affects both reads and writes. Does anyone know what's going on here? ------- You are receiving this mail because: ------- You are on the CC list for the bug, or are watching someone who is. - To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
