In that page you should also check the raw output of dd, showing in the last column the IOPs.
Olaf Il 18 giugno 2018 08:50:16 CEST, priyadarshan <priyadars...@scs.re> ha scritto: > >> On 18 Jun 2018, at 08:27, Oliver Weinmann ><oliver.weinm...@icloud.com> wrote: >> >> Hi, >> >> we have a HGST4u60 SATA JBOD with 24 x 10TB disks. I just saw that >back then when we created the pool we only cared about disk space and >so we created a raidz2 pool with all 24disks in one vdev. I have the >impression that this is cool for disk space but is really bad for IO >since this only provides the IO of a single disk. We only use it for >backups and cold CIFS data but I have the impression that especially >running a single VEEAM backup copy job really maxes out the IO. In our >case the VEEAM backup copy job reads and writes the data from the >storage. Now I wonder if it makes sense to restructure the Pool. I have >to admit that I don't have any other system with a lot of disk space so >I can't simply mirror the snapshots to another system and recreate the >pool from scratch. >> >> Would adding two ZIL SSDs improve performance? >> >> Any help is much appreciated. >> >> Best Regards, >> Oliver > >Hi, > >I would be interested to know as well. > >Sometimes we have same issue: need for large space vs need to optmise >for speed (read, write, or both). We also are using, at the moment, >10TB disks, although never do RAID-Z2 with more than 10 disks. > >This page has some testing that was useful to us: >https://calomel.org/zfs_raid_speed_capacity.html > >Section «Spinning platter hard drive raids» has your use case (although >4TB, not 10TB): > >24x 4TB, 12 striped mirrors, 45.2 TB, w=696MB/s , rw=144MB/s , >r=898MB/s >24x 4TB, raidz (raid5), 86.4 TB, w=567MB/s , rw=198MB/s , >r=1304MB/s >24x 4TB, raidz2 (raid6), 82.0 TB, w=434MB/s , rw=189MB/s , >r=1063MB/s >24x 4TB, raidz3 (raid7), 78.1 TB, w=405MB/s , rw=180MB/s , >r=1117MB/s >24x 4TB, striped raid0, 90.4 TB, w=692MB/s , rw=260MB/s , >r=1377MB/s > >Different adapters/disks will change the results, but I do not thing >ratio will change much. > >It would be interesting to see how ZIL would affect that. > > >Priyadarshan >_______________________________________________ >OmniOS-discuss mailing list >OmniOS-discuss@lists.omniti.com >http://lists.omniti.com/mailman/listinfo/omnios-discuss _______________________________________________ OmniOS-discuss mailing list OmniOS-discuss@lists.omniti.com http://lists.omniti.com/mailman/listinfo/omnios-discuss
