On Tue, 18 Mar 2014, Yuanhan Liu wrote: > On Sat, Mar 15, 2014 at 08:56:10PM -0700, Hugh Dickins wrote: > > On Fri, 14 Mar 2014, Mel Gorman wrote: > > > > > > You say it's already been tested for months but it would be nice if the > > > workload that generated this thread was also tested. > > > > Yes indeed: Yuanhan, do you have time to try this patch for your > > testcase? I'm hoping it will prove at least as effective as your > > own suggested patch, but please let us know what you find - thanks. > > Hi Hugh, > > Sure, and sorry to tell you that this patch introduced another half > performance descrease from avg 60 MB/s to 30 MB/s in this testcase. Thanks a lot for trying it out. I had been hoping that everything would be wonderful, and I wouldn't have think at all about what's going on. You have made me sad :( but I can't blame your honesty! I'll have to think a little after all, about your test, and Mel's pertinent questions: I'll come back to you, nothing to say right now. Hugh > > Moreover, the dd throughput for each process was steady before, however, > it's quite bumpy from 20 MB/s to 40 MB/s w/ this patch applied, and thus > got a avg of 30 MB/s: > > 11327188992 bytes (11 GB) copied, 300.014 s, 37.8 MB/s > 1809373+0 records in > 1809372+0 records out > 7411187712 bytes (7.4 GB) copied, 300.008 s, 24.7 MB/s > 3068285+0 records in > 3068284+0 records out > 12567691264 bytes (13 GB) copied, 300.001 s, 41.9 MB/s > 1883877+0 records in > 1883876+0 records out > 7716356096 bytes (7.7 GB) copied, 300.002 s, 25.7 MB/s > 1807674+0 records in > 1807673+0 records out > 7404228608 bytes (7.4 GB) copied, 300.024 s, 24.7 MB/s > 1796473+0 records in > 1796472+0 records out > 7358349312 bytes (7.4 GB) copied, 300.008 s, 24.5 MB/s > 1905655+0 records in > 1905654+0 records out > 7805558784 bytes (7.8 GB) copied, 300.016 s, 26.0 MB/s > 2819168+0 records in > 2819167+0 records out > 11547308032 bytes (12 GB) copied, 300.025 s, 38.5 MB/s > 1848381+0 records in > 1848380+0 records out > 7570964480 bytes (7.6 GB) copied, 300.005 s, 25.2 MB/s > 3023133+0 records in > 3023132+0 records out > 12382748672 bytes (12 GB) copied, 300.024 s, 41.3 MB/s > 1714585+0 records in > 1714584+0 records out > 7022936064 bytes (7.0 GB) copied, 300.011 s, 23.4 MB/s > 1835132+0 records in > 1835131+0 records out > 7516696576 bytes (7.5 GB) copied, 299.998 s, 25.1 MB/s > 1733341+0 records in > > > --yliu > -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>