[OpenIndiana-discuss] SCSI SSD Performance

[Grant Albitz]

Hi I am trying to track down a performance issue with my setup.

I have 24 ssds in 6 vdevs (4 drives per) that are then striped. Essentially a raid50. Originally I had a perc h310 and saw similar numbers. I have since switched to a perch h710 and have each drive in raid 0 and presented to the os. In both cases the numbers are the same. I also tried 8 devices per vdev with only 3 vdevs and the numbers were also the same.I am thinking I am tracking down a zfs tunable but I am not sure what to try. My reads are ½ of my writes. Given a raid 50 I was expecting the opposite. The volume is being presented as an iscsi lun. The benchmarks below were run from a vmware guest. The esxi host is connected to the iscsi target via a 10g interface (direct connection).

There is no l2arche, but the entire pool is ssd..


-----------------------------------------------------------------------
CrystalDiskMark 3.0.2 x64 (C) 2007-2013 hiyohiyo
                           Crystal Dew World : http://crystalmark.info/
-----------------------------------------------------------------------
* MB/s = 1,000,000 byte/s [SATA/300 = 300,000,000 byte/s]

           Sequential Read :   361.519 MB/s
          Sequential Write :   690.307 MB/s
         Random Read 512KB :   298.297 MB/s
        Random Write 512KB :   517.125 MB/s
    Random Read 4KB (QD=1) :    19.731 MB/s [  4817.0 IOPS]
   Random Write 4KB (QD=1) :    18.025 MB/s [  4400.7 IOPS]
   Random Read 4KB (QD=32) :   174.766 MB/s [ 42667.5 IOPS]
  Random Write 4KB (QD=32) :   209.150 MB/s [ 51061.9 IOPS]

  Test : 50 MB [C: 10.8% (32.3/299.7 GB)] (x1) <0Fill>
  Date : 2013/02/16 11:07:10
    OS : Windows 8 Professional [6.2 Build 9200] (x64)



-----------------------------------------------------------------------
CrystalDiskMark 3.0.2 x64 (C) 2007-2013 hiyohiyo
                           Crystal Dew World : http://crystalmark.info/
-----------------------------------------------------------------------
* MB/s = 1,000,000 byte/s [SATA/300 = 300,000,000 byte/s]

           Sequential Read :   351.646 MB/s
          Sequential Write :   652.356 MB/s
         Random Read 512KB :   287.946 MB/s
        Random Write 512KB :   468.861 MB/s
    Random Read 4KB (QD=1) :    19.915 MB/s [  4862.2 IOPS]
   Random Write 4KB (QD=1) :    17.263 MB/s [  4214.7 IOPS]
   Random Read 4KB (QD=32) :   169.849 MB/s [ 41466.9 IOPS]
  Random Write 4KB (QD=32) :   189.730 MB/s [ 46320.8 IOPS]

  Test : 100 MB [C: 10.8% (32.2/299.7 GB)] (x1) <0Fill>
  Date : 2013/02/16 11:05:07
    OS : Windows 8 Professional [6.2 Build 9200] (x64)