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Unable to enable Write-Caching on Windows 7 x64

This is bit of an odd one. I have a lab server that wasn't getting the Write performance that I would expect. (Based on tests with HDtune) The Controller itself states that Write-Caching is set to enabled. However the OS states that it is not and cannot enable it for the disk.

I also have a 3ware 9550 controller installed with a RAID 5 array and it allows caching to be enabled on the controller and within the OS just fine.

I took an image of the partition on the RAID 10 Array and then blew it away. I recreated the Array making sure that write cache was enabled upon creation. Same Behavior.

The system spec's are as follows:

Motherboard: X7DAE
http://www.supermicro.com/products/motherboard/xeon1333/5000x/x7dae.cfm

SAS Raid Controller: Adaptec 4800SAS with attached Battery Backup
https://www.adaptec.com/en-us/support/raid/sas_raid/sas-4800/

Array: 4 x 15K SAS in RAID 10 - 256k clusters

Windows 7 Pro x64

See attached to see the screenshots from the controller and the OS. I would deduce that enabling and controlling write-caching on the controller would then prevent one from doing the same within the OS. But as I said this is not the case on the 3Ware (LSI) controller.

So shouldn't I be able to modify the write-caching policy of the Disk from the OS? Or is this specific to to Vendor / Driver?
Logical-disk1.JPG
Logical-disk2.JPG
disk0.JPG
windows.JPG

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Member_2_231077

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EagleMed-IT

ASKER

The battery was actually just installed last week and took a few days to fully charge. The thing that bothered me was that even on the controller the MODE says disabled, but the write cache setting says ENABLED w/battery. The controller reports no issues with the battery (optimal) @ 100% charged.

Changing the write cache SETTING on the controller shows no different result when testing with HD tune. Write cache ENABLED or DISABLED yield the same stats.

That leads me to believe that the MODE is critical here. Even though I have the setting @ write cache enabled with battery, the controller is still running with cache mode = disabled.

I tried using the controller command line tool to force the mode to WB (write back) but it says its already configured this way.

Member_2_231077

and if you use arconf getconfig al does it show as temporarily disabled same as the GUI? It may just be a bug and needs a power cycle to realise the battery's charged or simply disabling and enabling (but I think you've tried that).

EagleMed-IT

ASKER

Thanks for the replies andy. Your command sent me in the right direction, its actually:

ARCCONF GETCONFIG 1 AL

I exported the config and as you can see it does show the same as the GUI. I may need to see if Adaptec can provide insight into this, though I'm not entirely sure they will offer support on it.
4800SAS.txt

Member_2_231077

With the disks set to write-back I'm surprised it even bothers about reporting the battery status since data loss will occur on sudden power loss regardless.

EagleMed-IT

ASKER

I believe the controller set the disks to WB but I can manually set them to WT if you think this is highly risky. Its mainly test storage for iSCSI Datastores.

Member_2_231077

If it's just test you can pull out all the stops, but enabling the disk write cache by setting them to WB means the disk will tell the controller the data is committed when it is only in the disk cache.

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EagleMed-IT

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EagleMed-IT

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Not resolved but no new information can be provided at this time.