On Wed, Feb 08, 2012 at 08:51:11PM +0800, Hillf Danton wrote: > On Tue, Feb 7, 2012 at 9:27 PM, Mel Gorman <mgorman@xxxxxxx> wrote: > > On Tue, Feb 07, 2012 at 08:45:18PM +0800, Hillf Danton wrote: > >> If it is feasible to bypass hang by tuning min_mem_kbytes, > > > > No. Increasing or descreasing min_free_kbytes changes the timing but it > > will still hang. > > > >> things may > >> become simpler if NICs are also tagged. > > > > That would mean making changes to every driver and they do not necessarily > > know what higher level protocol like TCP they are transmitting. How is > > that simpler? What is the benefit? > > > The benefit is to avoid allocating sock buffer in softirq by recycling, > then the changes in VM core maybe less. > The VM is responsible for swapping. It's reasonable that the core VM has responsibility for it without trying to shove complexity into drivers or elsewhere unnecessarily. I see some benefit in following on by recycling some skbs and only allocating from softirq if no recycled skbs are available. That potentially improves performance but I do not recycling as a replacement. -- Mel Gorman SUSE Labs -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>