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Date: Tue, 25 Sep 2001 13:15:28 -0700 (PDT)
Message-Id: <20010925.131528.78383994.davem@redhat.com>
To: marcelo@conectiva.com.br
Cc: andrea@suse.de, torvalds@transmeta.com, linux-kernel@vger.kernel.org
Subject: Re: Locking comment on shrink_caches()
From: "David S. Miller" <davem@redhat.com>
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   From: Marcelo Tosatti <marcelo@conectiva.com.br>
   Date: Tue, 25 Sep 2001 15:40:23 -0300 (BRT)
   
   We can simply lock the pagecachelock and the pagemap_lru_lock at the
   beginning of the cleaning function. page_launder() use to do that.
   
   Thats why I asked Andrea if there was long hold times by shrink_caches().
   
Ok, I see.

I do think it's silly to hold the pagecache_lock during pure scanning
activities of shrink_caches().

It is known that pagecache_lock is the biggest scalability issue on
large SMP systems, and thus the page cache locking patches Ingo and
myself did.

Franks a lot,
David S. Miller
davem@redhat.com