Simple question: is it safe to enable the disk write cache when using ZFS? This message posted from opensolaris.org
Hello UNIX,
Monday, June 19, 2006, 10:02:03 AM, you wrote:
Ua> Simple question: is it safe to enable the disk write cache when using
ZFS?
As ZFS should send proper ioctl to flush cache after each transaction
group it should be safe.
Actually if you give ZFS whole disk it will try to enable write cache
on that disk anyway.
--
Best regards,
Robert mailto:rmilkowski at task.gda.pl
http://milek.blogspot.com
> As ZFS should send proper ioctl to flush cache after > each transaction > group it should be safe. > > Actually if you give ZFS whole disk it will try to > enable write cache > on that disk anyway.Thanks for the answer, that''s very good news indeed! This message posted from opensolaris.org
Robert Milkowski schrieb:> Hello UNIX, > > Monday, June 19, 2006, 10:02:03 AM, you wrote: > > Ua> Simple question: is it safe to enable the disk write cache when using ZFS? > > As ZFS should send proper ioctl to flush cache after each transaction > group it should be safe. > > Actually if you give ZFS whole disk it will try to enable write cache > on that disk anyway.What about ATA disks? Currently (at least on x86) the ata driver enables the write cache unconditionally on each drive and doesn''t support the ioctl to flush the cache (although the function is already there). Daniel
> What about ATA disks? > > Currently (at least on x86) the ata driver enables the write cache > unconditionally on each drive and doesn''t support the ioctl to flush the cache > (although the function is already there).DKIOCFLUSHWRITECACHE? It is implemented here, for x86 ata: http://cvs.opensolaris.org/source/xref/on/usr/src/uts/intel/io/dktp/dcdev/dadk.c#703 This message posted from opensolaris.org