The objective of this paper is to observe performance gains that can be achieved in a Hyper-V virtualized computing environment with the application of a host-based SSD cache controlled using SanDisk® DAS Cache 1.3.1 software.
The objective of this paper is to present performance gains that can be achieved in a virtualized computing environment with the application of a host-based SSD cache enabled by the FlashSoft® Software from SanDisk. VMware ESXi™ hypervisor software was installed on a host server, and multiple VMs were configured. FlashSoft software from SanDisk was used to provide a host-based cache to accelerate workloads running on the VMs. The benchmark program fio.exe was used to generate a synthetic workload and measure performance. For configurations with one, five, and ten VMs, read performance measured while using the host-based SSD cache was compared to that of baseline configurations using all-HDD storage with no caching.
Some key observations about this testing include:
The servers under test were configured as follows:
Figure 1. Server configuration used for testing.
This study used the fio.exe (Flexible IO) benchmarking and workload simulation tool to generate a synthetic workload and measure performance. The following benchmark settings were used for all testing:
Both IOPS and latency were measured for a random read workload. In tests with multiple VMs IOPS were summed for all VMs measured, while latency was averaged across all VMs measured.
The following contains the fio.exe script used for all testing. This script specifies an I/O block size of 4KB, 4KB block alignment, and a random read I/O pattern.
[global] filename=/dev/disk/by-id/scsi-36000c299ce448d79a0601877915ae456 ioengine=libaio exitall norandommap randrepeat=0 group_reporting direct=1 ramp_time=5 runtime=120 time_based iodepth=32 numjobs=8 #random_distribution=pareto:0.1 [jobs1] name=density readwrite=randread bs=4k ba=4k
Table 1. fio.exe script used for testing.
The following testing procedures were used:
In order to consistently measure the performance of the cached configurations, the cache was completely flushed after each individual test. In addition, the cache was “pre-conditioned” immediately before conducting each benchmark test using the same warmup workload.
When testing multiple VMs, performance was measured on all VMs concurrently.
The benchmark results for tests run with 1, 5, and 10 VMs. The baseline configuration used all-HDD storage with no caching to the SSD. The accelerated configuration used the SSD cache and FlashSoft software with write-through cache enabled. For tests with multiple VMs, read IOPS were summed across all VMs and read latency was averaged across all VMs.
|Total Read IOPS||Average Read Latency (msec)|
Figure 2 shows a graphical representation of the total read IOPS for the baseline and accelerated storage configurations. For tests with multiple VMs, read IOPS were summed across all VMs being tested.
Figure 3 shows a graphical representation of the average read latency comparison of the baseline and accelerated storage configurations. In tests with multiple VMs, latency values were averaged for all VMs.
Data measured in these tests illustrate how FlashSoft software can significantly improve read performance for VMs running in a VMware ESXi environment as compared to traditional all-HDD backend storage. Total read performance increased 10.86 times for tests with 1 VM running with the SSD write-through cache enabled as compared to the baseline configuration with no caching. Tests with 5 and 10 VMs showed performance increases of over 30 times for the accelerated configuration as compared to the baseline configuration. Average read latency showed similar improvements, decreasing by 10.86 times for tests with 1 VM, and decreasing by over 29 times for tests with 5 and 10 VMs when the workload was accelerated with the SSD cache and FlashSoft software.
The tests described in this report were conducted with small data sets using the fio.exe benchmark-testing tool. Although the tests were constructed to simulate conditions typically encountered in the field and to generate data that reveal application performance, the tests can only be considered a demonstration of the capability of FlashSoft software—the data should not be regarded as the full performance potential of FlashSoft software. The actual performance of any caching solution is highly dependent upon the workload and the computing environment in which it is used.
Specifications are subject to change.
Whether you'd like to ask a few initial questions or are ready to discuss a SanDisk solution tailored to your organizations's needs, the SanDisk sales team is standing by to help.
We're happy to answer your questions, so please fill out the form below so we can get started. If you need to talk to the sales team immediately, please phone: 800.578.6007
Thank you. We have received your request.