Ok.
Going to write a patch and send you to test RSN.
On Fri, 16 Mar 2001, Ingo Molnar wrote:
>
> On Thu, 15 Mar 2001, Marcelo Tosatti wrote:
>
> > The old create_bounce code used to set PF_MEMALLOC on the task flags
> > and call wakeup_bdflush(1) in case GFP_BUFFER page allocation failed.
> > That was broken because flush_dirty_buffers() could try to flush a
> > buffer pointing to highmem page, which would end up in create_bounce
> > again, but with PF_MEMALLOC.
> >
> > Have you tried to make flush_dirty_buffers() only flush buffers
> > pointing to lowmem pages in case the caller wants it to do so?
>
> this makes sense too - although an emergency pool of some sort never
> hurts, given that highmem buffers cannot be written out without allocating
> bounce buffers. (this makes them more volatile wrt. resource shortages
> than lowmem buffers.) Also, there is no guarantee that flushing lowmem
> buffers yields any free pages.
>
> > This way you can call flush_dirty_buffers() with the guarantee you're
> > going to free useful (lowmem) memory. This also throttles high mem
> > writes giving priority to low mem ones.
>
> yep, i think we should do this in addition to the emergency pool thing, it
> should improve balance.
>
> Ingo
>
-
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 : Fri Mar 23 2001 - 21:00:08 EST