Now NetApp performs server-side caching too

In addition to existing caching technologies, such as Flex Cache and Flex Pool, August 21^st, 2012 NetApp announced the Flash Accel solution which speeds application performance using server-side cache for storing frequently accessed data working with NetApp storage arrays.

The Flash Accel is the software leveraging the existing SSD and PCIe flash memory hardware installed into the servers. Will be supported the SSD and PCI-e flash memory products of Server Partner Caching Alliance members: Fusion-io, LSI, Micron, QLogic, SanDisk (FlashSoft), STEC and Virident.  Also the first version of Flash Accel will support Microsoft Windows Server 2003 and 2008 and VMware vSphere  5. (including DRS, HA and vMotion support).

The Flash Accel provides the following features:

• End-to-End Intelligent Data Coherency: if data blocks are changed on the backend array the Flash Accel will update the local cache accordingly. 
• Cache Persistency and Durability: Flash Accel preserves cache content consistently with applications in the event of server and VM reboot and crashes. After the server restart the cache content is checked and updated as the server is back on, what allows to have a warm cache after restart.

It’s also interesting that competing with other server-side caching solutions such as HP flash cache in Gen8 servers and EMC VFcache the Flash Accel is looking more open allowing to use hardware from different SSD and PCI-e flash memory vendors. 

But anyway, we shouldn’t also forget about other server-side caching solutions which are external storage system independent, e.g. FlashSoft from SANDisk , Nytro XD from LSI or ioTurbine from Fusion IO. 

Nimble Storage – performance and capacity scalability

New NS controllers as well as performance and capacity scalability features were announced August 5, 2012 by Nimble Storage.

Now the Nimble CS arrays can be scaled-out by:

• SSD cache upgrade by installing high capacity SSDs
• Adding up to the three ES1 disk shelves
• Non-disruptive upgrade from CS200 to CS400 controller
• Combine several SC arrays to the clustered storage

 

The clustering feature brings Nimble Storage to the higher market level allowing compete with high-midrange solutions from other storage vendors.

It’s possible to non-disruptively add storage controllers to the cluster and remove them from it (if there’s enough free space to save data from nodes that will be removed).  Each cluster can contain one of several Dynamic Storage Pools consisting of one or several storage controllers. Volume’s data is striped across all controllers in storage pool what provides the performance boost by adding controllers to the pool. After controller is added to or removed from the pool data is automatically rebalanced between storage controllers. Also pools can be merged and volumes can be migrated between storage pools transparently for applications. 

The VMware multipathing is performed by CIM and PSP provider installed on each ESX host server. The CIM monitors paths from host to the storage cluster nodes and provides information for PSP to choose the right path for IO operations. For Windows hosts the path management is performed by the Nimble Connection Manager (NCM). The scale-out Nimble Storage clusters can also be used with other operating systems but connections between hosts and storage controller ports need to be configured manually.

The combination of the Cache Accelerated Sequential Layout (CASL) architecture and storage clustering feature makes Nimble Storage one of the most interesting players on the storage market.