Re: [PATCH 2/3] Fix fsync livelock

[Arjan van de Ven]

On Sun, 5 Oct 2008 19:02:57 -0400 (EDT)
Mikulas Patocka <mpatocka@xxxxxxxxxx> wrote:

> > are you sure?
> > isn't the right fix to just walk the file pages only once?
> 
> It walks the pages only once --- and waits on each on them. But
> because new pages are contantly appearing under it, that "walk only
> once" becomes infinite loop (well, finite, until the whole disk is
> written).

well. fsync() promises that everything that's dirty at the time of the
call will hit the disk. That is not something you can compromise.
The only way out would be is to not allow new dirty during an fsync()...
which is imo even worse.

Submit them all in one go, then wait, should not be TOO bad. Unless a
lot was dirty already, but then you go back to "but it has to go to
disk".


-- 
Arjan van de Ven 	Intel Open Source Technology Centre
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