Dell’s Fluid Cache for DAS helps

Traditionally most of the IT organizations deploy servers such Dell’s PowerEdge R720 with lots of JBODS in Direct Attached Storage (DAS) environment and try to optimize the platform to achieve maximum user load, yet keeping the average response time (ART) as low as possible.  Growth in performance and storage size requirements becomes a cost prohibitive proposition most of the time in these deployments.


One of the ways to optimize these configurations is to add Flash SSDs and Fluid Cache for DAS in the solution mix.  This new solution then allows DAS to grow at comparatively cheaper cost yet plenty of room for performance hungry application Year over Year.


  • The new Fluid Cache for DAS based configuration when tested,  got following results
    • Fluid Cache based solution delivered approximately 60% more Transactions Per Second (TPS) compared to the baseline configuration
    • Fluid Cache based solution delivered approximately 95% better average response time over the baseline at 3100 user load
    • Fluid Cache for DAS based solution delivered approximately 34% more user load compared to the baseline.

Charts below depict these results:



With Fluid Cache based solution, it’s not necessary to fill-up all drive bays (in the test results above only two were used), the empty bays can be filled-in as needed ensuring future growth requirements for performance. Also, the backend storage capacity can scale at will, still room for future performance growth by increasing the caching capacity and yet get performance.


As an illustration, in a typical OLTP environment, Average Response Time (ART) required is 2 seconds. The test result below indicates, that for a concurrent user load of 3100, the baseline configuration allows ART up to 1.712 seconds; however with Fluid Cache based solution in the mix, the ART at 3100 user load is 0.09 seconds, giving a lot more room to grow the concurrent user load.



  • Summarizing the key benefits Fluid Cache delivers:
    • The cache pool supports read and write caching, accelerate writes, read-after-writes and re-reads while providing high availability, most solutions only impact random reads.
    • Offers cache management that is fully integrated with Dell storage management
    • Allows for the provisioning of cache for enhanced dataset performance and your storage to meet the need for greater capacity
    • The cache pool stays “warm” through reboots and the cache pool is highly available and resilient to failures
    • And above all, add Cache capacity on the fly using the hot pluggable Dell express Flash Drives.


For a demonstration of Fluid Cache for DAS, Dell TechCenter view this video recorded webinar on Fluid Cache for DAS 1.0.