On Mon, 2012-07-02 at 20:25 -0700, Yinghai Lu wrote: > > That means pageblock_order is always set to "MAX_ORDER - 1", not sure > > whether this is intended. And it has the same issue as IA64 of wasting > > memory if CONFIG_SPARSE is enabled. > > adding BenH, need to know if it is powerpc intended. > > > > > So it would be better to keep function set_pageblock_order(), it will > > fix the memory wasting on both IA64 and PowerPC. > > Should setup pageblock_order as early as possible to avoid confusing. Hrm, HPAGE_SHIFT is initially 0 because we only know at runtime what huge page sizes are going to be supported (if any). The business with pageblock_order is new to me and does look bogus today indeed. But not a huge deal either. Our MAX_ORDER is typically 9 (64K pages) or 13 (4K pages) and our standard huge page size is generally 16M so there isn't a big difference here. Still, maybe something worth looking into... Cheers, Ben. -- 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>