Rik van Riel wrote:
>
> On Thu, 7 Mar 2002, Andrew Morton wrote:
> > Daniel Phillips wrote:
> > >
> > > a GFP flag that says 'fail if this looks hard to get'.
> >
> > Something like that would provide a solution to the
> > readahead thrashing problem.
>
> Nope. Readahead pages are clean and very easy to evict, so
> it's still trivial to evict all the pages from another readahead
> window because everybody's readahead window is too large.
>
I was thinking an explicit GFP_READAHEAD and PG_readahead.
Where a GFP_READAHEAD allocation would fail if it can't
find any non-readahead pages. And it would fail if it
had to perform I/O.
That's not nice - it'd result in large LRU walks. But it'd
be better than the 10x slowdown which readahead thrashing
causes.
Any clever ideas?
-
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
This archive was generated by hypermail 2b29 : Thu Mar 07 2002 - 21:01:08 EST