On Mon, 21 Aug 2007, Andi Kleen wrote: > Christoph Lameter <[EMAIL PROTECTED]> writes: > > > Switch off PF_MEMALLOC during both direct and kswapd reclaim. > > > > This works because we are not holding any locks at that point because > > reclaim is essentially complete. The write occurs when the memory on > > the zones is at the high water mark so it is unlikely that writeout > > will get into trouble. If so then reclaim can be called recursively to > > reclaim more pages. > > What would stop multiple recursions in extreme low memory cases? Seems > risky to me and risking stack overflow. Perhaps define another flag to catch > that?
Right. I am not sure exactly how to handle that. There is also the issue of the writes being deferred. I thought maybe of using pdflush to writeout the pages? Maybe increase priority of the pdflush so that it runs immediately when notified. Shrink_page_list would gather the dirty pages in pvecs and then forward to a pdflush. That may make the whole thing much cleaner. Opinions? - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
