Hello,
I have a VM's stored on a RAMDISK. On the host the RAMDISK performs outstanding as far as IOPS and Read/Write speeds.
Here are the crystal Diskmark scores:
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CrystalDiskMark 3.0.1 x64 (C) 2007-2010 hiyohiyo
Crystal Dew World : http://crystalmark.info/
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* MB/s = 1,000,000 byte/s [SATA/300 = 300,000,000 byte/s]
Sequential Read : 2634.964 MB/s
Sequential Write : 2720.856 MB/s
Random Read 512KB : 2751.136 MB/s
Random Write 512KB : 2829.269 MB/s
Random Read 4KB (QD=1) : 900.765 MB/s [219913.4 IOPS]
Random Write 4KB (QD=1) : 744.167 MB/s [181681.4 IOPS]
Random Read 4KB (QD=32) : 801.563 MB/s [195694.2 IOPS]
Random Write 4KB (QD=32) : 708.118 MB/s [172880.4 IOPS]
Test : 50 MB [Z: 1.9% (37.8/1984.6 MB)] (x1)
Date : 2012/06/22 20:55:54
OS : Windows 7 Ultimate Edition [6.1 Build 7600] (x64)
However when I store my VM on the RAMDISK and boot into it I cant seem to get any where near the IOPS I get in the host OS. It seem to cap out at around 10k IOPS per second. I have also tried storing the VM's on SSD's that get more than 10K/s in the host but again top out at the magical 10k when booted into the VM running the same test. The logical side of me would say that the bottleneck is not in the hardware but the software. I have VT enabled on an 8 Core i7 and when I watch the CPU utilization it does not peak above 10% so I know its not a CPU bottleneck.
I have done this with multiple OS's for the VM's on 3 seperate machines host machines with all the same results around that magical 10K IOPS range. I do not have any configuration in my vmx file that would configure a IOPS cap. Is there a line I can add to the file that would unlock this? I have attached my vmx file for your review.
Anyone able to get more than 10K IOPS on their VM's?
