Smart Array P400

[Deldeb]

We are trying to set the Accelerator Ratio on our P400, but the only option that shows up is 100% Read 0% Write. Why are the other options not showing up. What other info do you neeed to help.

[Patrick Terlisten]

Hello,

is there a battery-backed write cache module attached to the P400? If not, please add a BBWC. Write cache is only enabled, if a BBWC is attached and fully loaded.

Best regards,
Patrick

[Deldeb]

No we dont but before we get it let me explain our prob. We are running SQL server 2005 on this box and it has a database that is replicated from a process Stratus server. When we try to re-sync tables, the process takes twice as long as the server we are trying to replace. It seems to be a disk utilization issue. When we turned on the Array cache it cut our time in half, but it is still slower. The raid is set up as raid 5 across 6 drives partitioned into 2 logical drives. Would being able to adjust the Ratio help?

[Pieter 't Hart]

If you want performance improvement for this replication installing BBWC will surely help.
as mentioned in the previous post you cannot enable write-back cache without the battery backup option installed

Alternatively you can consider converting your storage from Raid-5 to Raid-1 (or even Raid-1+0 in a 4 disk configuration).
You should choose raid-5 when capacity is important(less storage lost for redundancy), and raid-1 when speed is important.

[Deldeb]

Thanks for the info we got the bbwc and left it at the default 25% read and 75% write and our resync went from 2+ hours to 29 mins . Well worth the cost ..
Thanks

[EwongSPM]

do you have the part number for this and where did you order this part?

thanks