Hi all, [ .. ] >> >> Could you share us your patch for enabling global_tags/MQ on > megaraid_sas >> so that I can reproduce your test? >> >>> See below perf top data. "bt_iter" is consuming 4 times more CPU. >> >> Could you share us what the IOPS/CPU utilization effect is after > applying the >> patch V2? And your test script? > Regarding CPU utilization, I need to test one more time. Currently system > is in used. > > I run below fio test on total 24 SSDs expander attached. > > numactl -N 1 fio jbod.fio --rw=randread --iodepth=64 --bs=4k > --ioengine=libaio --rw=randread > > Performance dropped from 1.6 M IOPs to 770K IOPs. > This is basically what we've seen with earlier iterations. >> >> In theory, it shouldn't, because the HBA only supports HBA wide tags, >> that means the allocation has to share a HBA wide sbitmap no matte>> if global tags is used or not. >> >> Anyway, I will take a look at the performance test and data. >> >> >> Thanks, >> Ming > > > Megaraid_sas version of shared tag set. > Whee; thanks for that. I've just finished a patchset moving megarai_sas_fusion to embedded commands (and cutting down the size of 'struct megasas_cmd_fusion' by half :-), so that will come in just handy. Will give it a spin. Cheers, Hannes -- Dr. Hannes Reinecke Teamlead Storage & Networking hare@xxxxxxx +49 911 74053 688 SUSE LINUX GmbH, Maxfeldstr. 5, 90409 Nürnberg GF: F. Imendörffer, J. Smithard, J. Guild, D. Upmanyu, G. Norton HRB 21284 (AG Nürnberg)
