syncing accross all filesystems

[ceg]

tracking this issue from http://mailman.samwel.tk/pipermail/laptop-mode/2009-May/000120.html:

> laptop mode does a sync *across all file systems*. And
> that causes disk activity even on file systems that aren't being used
> much. Combine this with a laptop mode sync loop (as you are
> experiencing) and it becomes very annoying. :-/
>
>
> Well, that sounds like a fundamental flaw to me. I'm not sure why you
> would want to cause a write on a file system that has no data to write.

The assumption is that "sync" on a non-dirty fs is a no-op, so we can
simply sync all file systems. Apparently there are file systems that
break this, and then you get this kind of behaviour. :-/ I might want to
take this up with the fs developers...

[Ritesh Raj Sarraf (rrs)]

On 03/18/2011 06:30 PM, ceg wrote:
> The assumption is that "sync" on a non-dirty fs is a no-op, so we can
> simply sync all file systems. Apparently there are file systems that
> break this, and then you get this kind of behaviour. :-/ I might want to
> take this up with the fs developers...

I think Jens recently fixed it with the new per-backing-device writeback
mechanism.
Which kernel did you see this problem on?

--
Ritesh Raj Sarraf
RESEARCHUT - http://www.researchut.com
"Necessity is the mother of invention."

[ceg (ceg)]

The original report was with old ubuntu 9.10.