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Date: Sat, 5 Mar 2005 10:26:37 +1100
From: Peter Jeremy <PeterJeremy@optushome.com.au>
To: Jason Young <jyoung@ziggy.evelocity.net>
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cc: ALeine <aleine@austrosearch.net>
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Subject: Re: FUD about CGD and GBDE
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On Fri, 2005-Mar-04 16:37:05 -0600, Jason Young wrote:
>Why not put a flash chip into the drive's onboard electronics, of the same 
>size as the drive's cache, or the max possible size of all outstanding 
>cached writes?

That seems to be a better idea.  ISTR that once upon a time, vendors made
chips that had RAM shadowed by EEPROM which gave you the non-volatility
of EEPROM with the read/write performance of RAM.  Since the EEPROM was
written at once, you only needed 10-20 msec hold-up to preserve your RAM.

>At least some modern drives (seen this on HP/Compaq servers, etc) already 
>have flash-upgradeable firmware. It's just a matter of adding a little 
>more. You would use it only when power fails, so it's not like you would 
>wear it out.

I think that most modern drives have very little firmware in ROM  - just
a bootstrap - with most of the firmware stored on the disk itself.

-- 
Peter Jeremy