Re: Possible Idea with filesystem buffering.

Hans Reiser
2002-01-22T20:24:15Z

Andrew Morton wrote:

>Hans Reiser wrote:
>
>>So is there a consensus view that we need 2 calls, one to write a
>>particular page, and one to exert memory pressure, and the call to write
>>a particular page should only be used when we really need to write that
>>particular page?
>>
>
>Note that writepage() doesn't get used much. Most VM-initiated
>filesystem writeback activity is via try_to_release_page(), which
>has somewhat more vague and flexible semantics.
>
>And by bdflush, which I suspect tends to conflict with sync_page_buffers()
>under pressure. But that's a different problem.
>
>-
>
>
So the problem is that there is no coherently architected VM-to-FS
interface that has been articulated, and we need one.

So far we can identify that we need something to pressure the FS, and
something to ask for a particular page.

It might be desirable to pressure the FS more than one page aging at a
time for reasons of performance as Rik pointed out.

Any other design considerations?