Mt. Rainer - the server-side caching solution from Qlogic

Qlogic announced today the Mt. Rainier project, the server-side caching solution leveraging internal server SSD and PCI-e flash memory.

There are three possible Mt. Rainer cards configurations:

• An adapter with a separate flash card and PCIe link using an x4 cable drawing 25W
• An Adapter with a SAS IO port daughter card which links to internal server SSD
• An Adapter with an SSD daughter card with all power coming from the PCIe slot - 50W

From the OS point of view, the Mt. Rainer adapter is installed as a single adapter which needs only one driver, no additional drivers for PCIe cards or SSD devices will be required.

Another interesting feature is the Shared Caching feature which makes the shared cache available across multiple servers, all transparent to the host.  The Qlogic storage router technology is used for this feature. Each Mt. Rainier adapter can see what the other cards in the SAN zone are doing and know which LUNs have been cached. The SAN protocols are used to synchronize this information.

For the high availability purposes the Cache Mirroring feature can be used. The Cache Mirroring provides the synchronous peer-to-peer mirroring with write-back and write-through modes support.  

One of the most important things is that cache memory management, Cache Mirroring and Shared Caching don’t require host CPU resources – all operations are performed on the adapter’s ASIC level.

The first Mount Rainier products should be available in the first half of 2013.

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.