Andrew Morton wrote:
quoted text
> On Wed, 08 Aug 2007 14:10:15 -0700
> "Martin J. Bligh" <mbligh@mbligh.org> wrote:
> 
>> Why isn't this easily fixable by just adding an additional dirty
>> flag that says atime has changed? Then we only cause a write
>> when we remove the inode from the inode cache, if only atime
>> is updated.
> 
> I think that could be made to work, and it would fix the performance
> issue.
> 
> It is a behaviour change.  At present ext3 (for example) commits everything
> every five seconds.  After a change like this, a crash+recovery could cause
> a file's atime to go backwards by an arbitrarily large time interval - it
> could easily be months.
> 
I would think that (really) updating atime on open would be enough, 
hopefully without being too much. The "lazyatime" thing I was playing 
with only updated on open, final close, write, and fork.

I like the idea of updating once in a while, but one of the benefits of 
noatime is allowing drives to spin down via inactivity. If something 
does get done in the area of less but non-zero atime tracking, perhaps 
that could be taken into account. I have to check what "laptop_mode 
actually does, since my laptops are old installs.

-- 
Bill Davidsen <davidsen@tmr.com>
   "We have more to fear from the bungling of the incompetent than from
the machinations of the wicked."  - from Slashdot

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