On Thu, Jun 4, 2015 at 5:06 PM, Mike Snitzer <snitzer@xxxxxxxxxx> wrote: > On Thu, Jun 04 2015 at 6:21pm -0400, > Ming Lin <mlin@xxxxxxxxxx> wrote: > >> On Thu, Jun 4, 2015 at 2:06 PM, Mike Snitzer <snitzer@xxxxxxxxxx> wrote: >> > >> > We need to test on large HW raid setups like a Netapp filer (or even >> > local SAS drives connected via some SAS controller). Like a 8+2 drive >> > RAID6 or 8+1 RAID5 setup. Testing with MD raid on JBOD setups with 8 >> > devices is also useful. It is larger RAID setups that will be more >> > sensitive to IO sizes being properly aligned on RAID stripe and/or chunk >> > size boundaries. >> >> I'll test it on large HW raid setup. >> >> Here is HW RAID5 setup with 19 278G HDDs on Dell R730xd(2sockets/48 >> logical cpus/264G mem). >> http://minggr.net/pub/20150604/hw_raid5.jpg >> >> The stripe size is 64K. >> >> I'm going to test ext4/btrfs/xfs on it. >> "bs" set to 1216k(64K * 19 = 1216k) >> and run 48 jobs. > > Definitely an odd blocksize (though 1280K full stripe is pretty common > for 10+2 HW RAID6 w/ 128K chunk size). I can change it to 10 HDDs HW RAID6 w/ 128K chunk size, then use bs=1280K > >> [global] >> ioengine=libaio >> iodepth=64 >> direct=1 >> runtime=1800 >> time_based >> group_reporting >> numjobs=48 >> rw=read >> >> [job1] >> bs=1216K >> directory=/mnt >> size=1G > > How does time_based relate to size=1G? It'll rewrite the same 1 gig > file repeatedly? Above job file is for read. For write, I think so. Do is make sense for performance test? > >> Or do you have other suggestions of what tests I should run? > > You're welcome to run this job but I'll also check with others here to > see what fio jobs we used in the recent past when assessing performance > of the dm-crypt parallelization changes. That's very helpful. > > Also, a lot of care needs to be taken to eliminate jitter in the system > while the test is running. We got a lot of good insight from Bart Van > Assche on that and put it to practice. I'll see if we can (re)summarize > that too. Very helpful too. Thanks. > > Mike -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
