KAMEZAWA Hiroyuki wrote: > This is just an RFC...test is not enough yet. > > I know it's merge window..this post is just for sharing idea. > > This patch merges pc->flags and pc->mem_cgroup into a word. Then, > memcg's overhead will be 8bytes per page(4096bytes?). > > Because this patch will affect all memory cgroup developers, I'd like to > show patches before MM Summit. I think we can agree the direction to > reduce size of page_cgroup..and finally integrate into 'struct page' > (and remove cgroup_disable= boot option...) > > Patch 1/3 - introduce pc_to_mem_cgroup and hide pc->mem_cgroup > Patch 2/3 - remove pc->mem_cgroup > Patch 3/3 - remove memory barriers. > > I'm now wondering when this change should be merged.... > This is cool, but maybe we should skip this temporary step and merge all this stuff into page->flags. I think we can replace zone-id and node-id in page->flags with cumulative dynamically allocated lruvec-id, so there will be enough space for hundred cgroups even on 32-bit systems. After lru_lock splitting page to lruvec translation will be much frequently used than page to zone, so page->zone and page->node translations can be implemented as page->lruvec->zone and page->lruvec->node. -- 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>