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<p class="MsoNormal">Hi I am trying to track down a performance issue with my setup.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">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).<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">There is no l2arche, but the entire pool is ssd.. <o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">-----------------------------------------------------------------------<o:p></o:p></p>
<p class="MsoNormal">CrystalDiskMark 3.0.2 x64 (C) 2007-2013 hiyohiyo<o:p></o:p></p>
<p class="MsoNormal"> Crystal Dew World : http://crystalmark.info/<o:p></o:p></p>
<p class="MsoNormal">-----------------------------------------------------------------------<o:p></o:p></p>
<p class="MsoNormal">* MB/s = 1,000,000 byte/s [SATA/300 = 300,000,000 byte/s]<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"> Sequential Read : 361.519 MB/s<o:p></o:p></p>
<p class="MsoNormal"> Sequential Write : 690.307 MB/s<o:p></o:p></p>
<p class="MsoNormal"> Random Read 512KB : 298.297 MB/s<o:p></o:p></p>
<p class="MsoNormal"> Random Write 512KB : 517.125 MB/s<o:p></o:p></p>
<p class="MsoNormal"> Random Read 4KB (QD=1) : 19.731 MB/s [ 4817.0 IOPS]<o:p></o:p></p>
<p class="MsoNormal"> Random Write 4KB (QD=1) : 18.025 MB/s [ 4400.7 IOPS]<o:p></o:p></p>
<p class="MsoNormal"> Random Read 4KB (QD=32) : 174.766 MB/s [ 42667.5 IOPS]<o:p></o:p></p>
<p class="MsoNormal"> Random Write 4KB (QD=32) : 209.150 MB/s [ 51061.9 IOPS]<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"> Test : 50 MB [C: 10.8% (32.3/299.7 GB)] (x1) <0Fill><o:p></o:p></p>
<p class="MsoNormal"> Date : 2013/02/16 11:07:10<o:p></o:p></p>
<p class="MsoNormal"> OS : Windows 8 Professional [6.2 Build 9200] (x64)<o:p></o:p></p>
<p class="MsoNormal"> <o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">-----------------------------------------------------------------------<o:p></o:p></p>
<p class="MsoNormal">CrystalDiskMark 3.0.2 x64 (C) 2007-2013 hiyohiyo<o:p></o:p></p>
<p class="MsoNormal"> Crystal Dew World : http://crystalmark.info/<o:p></o:p></p>
<p class="MsoNormal">-----------------------------------------------------------------------<o:p></o:p></p>
<p class="MsoNormal">* MB/s = 1,000,000 byte/s [SATA/300 = 300,000,000 byte/s]<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"> Sequential Read : 351.646 MB/s<o:p></o:p></p>
<p class="MsoNormal"> Sequential Write : 652.356 MB/s<o:p></o:p></p>
<p class="MsoNormal"> Random Read 512KB : 287.946 MB/s<o:p></o:p></p>
<p class="MsoNormal"> Random Write 512KB : 468.861 MB/s<o:p></o:p></p>
<p class="MsoNormal"> Random Read 4KB (QD=1) : 19.915 MB/s [ 4862.2 IOPS]<o:p></o:p></p>
<p class="MsoNormal"> Random Write 4KB (QD=1) : 17.263 MB/s [ 4214.7 IOPS]<o:p></o:p></p>
<p class="MsoNormal"> Random Read 4KB (QD=32) : 169.849 MB/s [ 41466.9 IOPS]<o:p></o:p></p>
<p class="MsoNormal"> Random Write 4KB (QD=32) : 189.730 MB/s [ 46320.8 IOPS]<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"> Test : 100 MB [C: 10.8% (32.2/299.7 GB)] (x1) <0Fill><o:p></o:p></p>
<p class="MsoNormal"> Date : 2013/02/16 11:05:07<o:p></o:p></p>
<p class="MsoNormal"> OS : Windows 8 Professional [6.2 Build 9200] (x64)<o:p></o:p></p>
<p class="MsoNormal"> <o:p></o:p></p>
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