lkml.org 
[lkml]   [2022]   [Mar]   [31]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH] block/psi: make PSI annotations of submit_bio only work for file pages
On Wed, Mar 30, 2022 at 12:17:09PM -0400, Johannes Weiner wrote:
> It's add_to_page_cache_lru() that sets the flag.
>
> Basically, when a PageWorkingset (hot) page gets reclaimed, the bit is
> stored in the vacated tree slot. When the entry is brought back in,
> add_to_page_cache_lru() transfers it to the newly allocated page.

Ok. In this case my patch didn't quite do the right thing for readahead
either. But that does leave a question for the btrfs compressed
case, which only adds extra pages to a read to readahad a bigger
cluster size - that is these pages are not read at the request of the
VM. Does it really make sense to do PSI accounting for them in that
case?

\
 
 \ /
  Last update: 2022-03-31 07:16    [W:0.183 / U:0.484 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site