On Sun, Mar 20, 2011 at 07:37:02PM -0700, Hugh Dickins wrote: > On Sun, 20 Mar 2011, Andrea Arcangeli wrote: > > > > Interesting that slab allocates with order > 0 an object that is <4096 > > bytes. Is this related to slab_break_gfp_order? > > No, it's SLUB I'm using (partly for its excellent debugging, partly > to trigger issues like this). Remember, that's SLUB's great weakness, > that for optimal efficiency it relies upon higher order pages than you'd > expect. It's much better since Christoph put in the ORDER_FALLBACK, but > still makes a first attempt for a higher order page, which is liable to > stir up page_alloc more than we'd like. Ah ok, that explains it... I didn't realize you used SLUB sorry. I use SLAB as it's measurably faster in most workloads even on larger servers (but it will consume more memory on with an huge number of cpus, up to 128 CPUs it's no big deal). My cellphone uses SLUB though (kabi issues with evil rfs.ko or I would have switched already). -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxxx 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>