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Re: understanding speculative preallocation

To: Jason Rosenberg <jbr@xxxxxxxxxxxx>
Subject: Re: understanding speculative preallocation
From: Dave Chinner <david@xxxxxxxxxxxxx>
Date: Mon, 29 Jul 2013 10:04:18 +1000
Cc: Ben Myers <bpm@xxxxxxx>, stan@xxxxxxxxxxxxxxxxx, xfs@xxxxxxxxxxx
Delivered-to: xfs@xxxxxxxxxxx
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User-agent: Mutt/1.5.21 (2010-09-15)
On Sat, Jul 27, 2013 at 10:19:17PM -0400, Jason Rosenberg wrote:
> Thanks Dave,
> 
> The automatic prealloc removal, if no new writes after 5 minutes, sounds
> perfect for my use case.  But realistically, I'm not likely to get our org
> to push/find an os update just for this purpose too easily.
> 
> So, in the meantime, the question remains, assuming I have the version I
> have currently (dynamic preallocation, persists indefinitely until the file
> is closed/app quits, etc.), will this idea work (e.g. close the file after
> writing, then re-open read-only?). 

Maybe, maybe not. depends on whether the "don't remove prealloc"
heuristic was triggered at any time....

Cheers,

Dave.
-- 
Dave Chinner
david@xxxxxxxxxxxxx

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