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Turning off writeback cache on HSG80

 
Glenn Tice
Occasional Contributor

Turning off writeback cache on HSG80

We have a HSG80 (V86F-1) based array with a single controller and cache. I'm concerned that a controller/cache/ECB failure will result in data loss. If I turn off writeback caching (set d0 nowriteback_cache), will this ensure data integrity if the cache fails?
I presume that the host will only be informed that the write is sucessful when it is physically written.
3 REPLIES 3
Garry Fruth
Trusted Contributor

Re: Turning off writeback cache on HSG80

I agree with your interpretation.
Andreas Fassl
Frequent Advisor

Re: Turning off writeback cache on HSG80

Hi Glenn,

this is the reason you'll always should configure a system with a battery backup.
The battery has to be replaced on a regular base. If the battery is fine, you'll see no loss of data.

If you turn of write_back cache, you'll experience a major loss of write performance.

Best regards

Andreas
Uwe Zessin
Honored Contributor

Re: Turning off writeback cache on HSG80

A battery backup won't help if the controller or especially the cache module fails. NOWRITEBACK_CACHE will decrease the likelyhood of data corruption due to write holes.
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