zfs discuss - Oct 2010 - zil behavior

Hi!

i''m interested in zil''s behavior.

it''s my understanding that zil is used only when
synchronous(o_sync,o_dsync & directio) write io request.
then zil have written contents that system call is used by zil replay
when used by crashed.
is this correct?
It seems a large amount of io for system call.
I think maybe the real data is being written in zil.

Thanks a lot!
--
kei

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On Oct 27, 2010, at 8:08 PM, Kei Saito wrote:
> Hi!
> 
> i''m interested in zil''s behavior.
Start here:
http://blogs.sun.com/perrin/entry/the_lumberjack
> 
> it''s my understanding that zil is used only when
> synchronous(o_sync,o_dsync & directio) write io request.
> then zil have written contents that system call is used by zil replay
> when used by crashed.
> is this correct?
> It seems a large amount of io for system call.
> I think maybe the real data is being written in zil.
Yes, real data is written in the ZIL.
 -- richard

-- 
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