On (07/10/15 11:29), Minchan Kim wrote: > Good question. > > My worry was failure of order-0 page allocation in zram-swap path > when memory presssure is really heavy but I didn't insist to you > from sometime. The reason I changed my mind was > > 1. It's almost dead system if there is no order-0 page > 2. If old might be working well, it's not our design, just luck. I mean I find your argument that some level of fragmentation can be of use to be valid, to some degree. hm... by the way, unsigned long zs_malloc(struct zs_pool *pool, size_t size) { ... size += ZS_HANDLE_SIZE; class = pool->size_class[get_size_class_index(size)]; ... if (!first_page) { spin_unlock(&class->lock); first_page = alloc_zspage(class, pool->flags); if (unlikely(!first_page)) { free_handle(pool, handle); return 0; } ... I'm thinking now, does it make sense to try harder here? if we failed to alloc_zspage(), then may be we can try any of unused objects from a 'upper' (larger/next) class? there might be a plenty of them. -ss -- 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/ . Don't email: <a href=mailto:"dont@xxxxxxxxx"> email@xxxxxxxxx </a>