"Asai Thambi Samymuthu Pattrayasamy (asamymuthupa) [CONTRACTOR]" <asamymuthupa@xxxxxxxxxx> writes: > On 5/25/2011 8:36 AM, Jeff Moyer wrote: >> Asai Thambi S P<asamymuthupa@xxxxxxxxxx> writes: >> >>> On 5/11/2011 1:20 PM, Alan Cox wrote: >>>> So a bigger queue helped (at least in 2006). The AHCI driver can be >>>> taught your bigger queue easily enough. The question is where with a >>>> *current* kernel are any remaining bottlenecks if you do that and > how do >>>> we fix them. >>> >>> Attached image/table shows the performance numbers on current kernel. >>> >>> The main objectives of our new mtipx2xx driver are >>> 1.) highest performance (see attached image/table), >>> 2.) lowest CPU utilization, and >> >> Can you collect perf data to show why the ahci driver is taking up so >> much more CPU for the random I/O case? >> > > Collected the perf data for ahci driver. As the call graph is getting > distorted in the email, attaching the perf data call graph report. Thanks, Asai! I don't think cfq is the ideal I/O scheduler to be testing. Could you run again with deadline and/or noop and see how that changes your throughput and perf report? Also, just for completeness, could you tell us which kernel you ran this against? Thanks! Jeff -- To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
