In this three minute demo, I will demonstrate the significant impact the sequential storage feature has on overall storage performance. Random write workloads are especially difficult on storage systems and certainly those consisting of a RAID-5 configuration (one of the most common RAID types).
The demo consists of the following configuration:
Dell PowerEdge R720 Server
6x 300GB 15k SAS drives in RAID-5 connected via a H710P PERC RAID Controller
Single RAID volume in a single SSV disk pool
8x 10GB Virtual Disks created from the disk pool (presented over loopback)
Microsoft Windows Server 2012 R2
DataCore SANsymphony-V 10 PSP2
IOmeter Test Parameters
16 outstanding I/O’s per target
Pseudo Random Pattern
8KB block size 100% write/100% random workload
Watch the demo below (make sure you click on the HD button in the upper right hand corner)
What is happening here?
Simply put, SANsymphony-V is taking all the writes that are inbound and writing them in a “sequential” pattern. This sequential pattern is highly favorable to disk subsystems because it doesn’t require as much armature movement to perform the write function. SANsymphony-V is quite literally “just writing the data”. In other words, the seek time normally experienced when writing data to the disk with a random pattern is all together eliminated resulting in massive performance boost for applications that have any measurable amount of random write activity.