[lkml]   [2011]   [Sep]   [6]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: [PATCH 17/18] writeback: fix dirtied pages accounting on redirty
On Sun, 2011-09-04 at 09:53 +0800, Wu Fengguang wrote:
> De-account the accumulative dirty counters on page redirty.
> Page redirties (very common in ext4) will introduce mismatch between
> counters (a) and (b)
> a) NR_DIRTIED, BDI_DIRTIED, tsk->nr_dirtied
> This will introduce systematic errors in balanced_rate and result in
> dirty page position errors (ie. the dirty pages are no longer balanced
> around the global/bdi setpoints).

So wtf is ext4 doing? Shouldn't a page stay dirty until its written out?

That is, should we really frob around this behaviour or fix ext4 because
its on crack?

 \ /
  Last update: 2011-09-06 18:21    [from the cache]
©2003-2014 Jasper Spaans. hosted at Digital Ocean