Re: Possible Idea with filesystem buffering.

Rik van Riel
2002-01-21T00:49:01Z

On Mon, 21 Jan 2002, Hans Reiser wrote:

> Suppose we do what you ask, and always write the page (as well as some
> other pages) to disk. This will result in the filesystem cache as a
> whole receiving more pressure than other caches that only write one
> page in response to pressure. This is unbalanced, leads to some
> caches having shorter average page lifetimes than others, and it is
> therefor suboptimal. Yes?

If your ->writepage() writes pages to disk it just means
that reiserfs will be able to clean its pages faster than
the other filesystems.

This means the VM will not call reiserfs ->writepage() as
often as for the other filesystems, since more of the
pages it finds will already be clean and freeable.

I guess the only way to unbalance the caches is by actually
freeing pages in ->writepage, but I don't see any real reason
why you'd want to do that...

regards,

Rik
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