Partnership with Seagate – VirtuCache Host Cache To Improve the Performance of Seagate Array
San Mateo, CA. January 14, 2022.
Virtunet and Seagate have extended their original partnership from 2013 to bundle VirtuCache with Seagate Storage arrays.
Virtunet develops host side caching software for VMware.
Seagate manufactures hard drives, SSDs, and enterprise storage arrays.
Seagate’s Storage Arrays
Seagate arrays are some of the cheapest enterprise grade arrays on the market. This is because Seagate doesn’t use expensive x86 processors for storage controllers, instead Seagate manufactures its own storage controller microprocessor and the associated controller card called Gallium. This card is more like a RAID controller card than an x86 motherboard. It is cheaper than an x86 based storage controller board, but it is also slower. Gallium maxes out at about 200K IOPS for random small block IO.
This is where VirtuCache comes in. By caching all storage IO from VMs to ESXi host cache media (RAM or SSD), VirtuCache improves the storage performance of VMware VMs, and for any SAN storage array connected to ESXi hosts. VirtuCache is essentially offloading storage IO processing from SAN array controllers to ESXi hosts. As a result, the less powerful Seagate Gallium controllers are now not the storage bottleneck. With the help of VirtuCache much higher throughput / IOPS at lower latencies can be supported by the SAN infrastructure. VirtuCache essentially provides native RAM or NVME speeds regardless of how slow or congested the SAN gets.
List of Enterprise Features in the Seagate Array
Seagate arrays are branded as Seagate 3005, 4005, 5005. They are also rebranded by HPE as HPE MSA and by Dell as Dell ME4.
- They come in All-HDD, Hybrid, and All-Flash configurations. A 2u form factor array scales to 184TB All-Flash, 432TB All-HDD and Hybrid configuration. In a 5u form factor, it scales to 1.5PB in an all-HDD / Hybrid / all-SSD configuration.
- Support for 10gbps iSCSI, 16gbps FC.
- Supports all RAID levels and Erasure Coding.1
- Much like any enterprise grade array, it has redundant components to sustain failure of any one part – two controller boards, 4 ports across two NICs per controller, one management port per controller, and drives equally shared between the two controllers.
- Support for data at rest encryption.
- Support for Controller Snapshots and Replication between Seagate Arrays.
- Currently, there is no support for dedupe or compression.
The difference between the Seagate 3005, 4005, 5005 arrays is that in each increasing model number the Gallium processor is 15% more powerful.
Cost of VirtuCache and Seagate Arrays
VirtuCache software cost is listed here. The cost of a NVME SSD to be used as VirtuCache cache media is listed here.
Seagate All-Flash Array costs US 60-75 cents per GB of raw SSD storage capacity.
Support
Virtunet supports Seagate arrays and VirtuCache for a maximum of 8 years from purchase versus the standard 5 year support for enterprise hardware from other vendors.
Summary
Versus any other All-Flash array, the cost/GB of storage capacity and cost/IOPS for storage performance is much less with Seagate storage array paired with VirtuCache host cache.
Also, storage capacity and storage performance can be scaled up independently of each other.
1- Erasure Coding is increasingly replacing RAID, since it is quicker to rebuild failed drives with Erasure Coding when you have larger capacity drives. In Erasure Coding much like RAID6, your usable space is reduced by 2 drives, and you can sustain a loss of 2 drives.