Re: Disabling disk caches [Re: CVS commit: src/lib/libc/sys, re sync(1)]

[David Holland <dholland-tech%netbsd.org@localhost>]

On Wed, Mar 25, 2009 at 09:44:52PM +0000, Andrew Doran wrote:
 > I think we should:
 > 
 > (a) Automatically disable the disk write cache the moment a file system is
 >     mounted on the disk, unless that file system is known to handle caching.
 >     For our purposes, that leaves logging ffs and zfs (and whatever other
 >     modern file systems come along) with the cache enabled.

While technically this may be the right thing, it won't be popular.

(So, why doesn't sync flush the disk write cache?)

 > (b) Change mount to flush the disk cache as a test, if r/w mount. If we get
 >     an error, send a warning message to the log. This will help us to get
 >     broken disk drivers fixed.

That seems like a good idea.

-- 
David A. Holland
dholland%netbsd.org@localhost