300% is too much of a performance increase to assign completely to the write cache being enabled, although it does make a significant difference.  When the battery goes bad, the controller turns off write caching, and that is the source of the performance difference.  Unless you have a good and specific reason for disabling the cache (and I can't think of any good reasons), it should be enabled.  You can't force the controller to use the cache without the battery, besides it's dangerous to your data to use cache without a battery. "Bottom line is that I am aiming for the highest performance for read and writes, thank you all!" Bottom line ... enable write cache (write back) and replace batteries when needed (which should not be often).
Hey guys I was hoping someone out there had some information on what the best practices or best settings should be for these two configurations regarding a Dell 2950 with a PERC 5/i.  Senario 1 Dell 2950 Windows Server 2003 Enterprise 32BIT RAID 5 (5TB) Hardware RAID & Windows Dynamic Disk Configuration  PERC 5/i with battery  Current Virtual Disk Group Advanced Settings Virtual Disk 0 - Adaptive Read Ahead & Write Back Virtual Disk 1 - Adaptive Read Ahead & Write Back   Senario 2 Dell 2950 Windows Server 2003 Enterprise 32BIT RAID 5 (5TB) Hardware RAID & Windows Dynamic Disk Configuration  PERC 5/i with battery  Current Virtual Disk Group Advanced Settings Virtual Disk 0 - Adaptive Read Ahead & Write Through Virtual Disk 1 - Adaptive Read Ahead & Write Through   The second server as of now had a battery that failed and one is on the way. I would like to add that I just found out that a bad or dead battery kills the performance on the server's read and write speed. After replacing the battery on the first server I saw the performance increase at least 300% if not more. So this lead me to read a lot of posts by others but I could not find a solid post that states what the best configuration should be. So my questions are these...what is the best configuration for Virtual Disk Group Advanced Settings for MY servers above WITH a controller battery? Finally, what if I didn't want to use the battery what is recomended then? Is it better to use a battery or be without one? Bottom line is that I am aiming for the highest performance for read and writes, thank you all!
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