Comments on: Running VMware ESXi on a home lab HP Proliant ML115 G5 with a Dell PERC 5i Array Controller.

By: Ricardo

Ricardo — Sat, 19 Nov 2011 13:16:03 +0000

Hi,

Does that raid card works in VMware ESXi 5.0 ?

By: Kenneth Davis

Kenneth Davis — Wed, 20 Oct 2010 02:12:26 +0000

Thanks for the responses I will try it with the bbwc. So its back to ebay for me

By: James

James — Tue, 19 Oct 2010 22:32:54 +0000

Finding confirmation has proven difficult for the PERC, but I know that other RAID cards disable the cache which is on each HDD. If they didnt/dont, then a lost of power could lose the amount of cache * the number of HDD you have. (even a single 32 meg cache is a lot to lose out of a database, let along 8 drives worth or 256MB of missing data)
The solution here is to use a pool of battery backed up memory on the RAID card to take the place of the memory that is no longer used on the HDD.
Without this memory, the whole process crawls as the OS waits for the physical operation of commmitting the data to the disks plus losing some optimisations in processing order that cache can supply.
Again, I can only say for sure that he HP raid cards function in this manor as standard – however I find it hard to see that it could work any other way looking at the risks involved.

By: James Pearce

James Pearce — Tue, 19 Oct 2010 21:49:56 +0000

Hi Kenneth, my testing echos that of the comment below – the BBWC is required for ESX with any spinning storage unfortunately. HTH!

By: James

James — Tue, 19 Oct 2010 21:15:50 +0000

I am going to strongly *guess* yes – I have done a large amount of benchmarking with HP Raid cards, Even with 2 disk mirrors I have seen massive improvements with write perfomance with a BBWC

By: Kenneth Davis

Kenneth Davis — Tue, 19 Oct 2010 20:04:43 +0000

Is the BBWC needed for performance if going with raid 10? I already ordered the card but I am not sure if the bbwc is necessary.