>I agree. What I am asking is if we turn on the 4th level of >page tables, does anybody have an objection to 4/16k levels as opposed to >3/PAGE_SIZE plus a 4th cleanup to cover the entire address space?
Are there any other big system users now (or coming real soon) for whom 2**60 (with PAGE_SIZE=64k, 2**58 with PAGE_SIZE=16k) would be a major pain? You'd have to do some fancy footwork documenting and enforcing the PAGE_SIZE vs. PAGE_TABLE_LEVELS interactions (it would be bad to configure a 4K or 8K pagesize with a 4-level option that expected to allocate 16K for page tables). The PAGE_SIZE=64k 4/16k case requires you to deal with partial pages on the quicklists (or in the slab if you go that route). The slab code knows how to coalesce and free such sub-pages under memory pressure (though fragmentation may make it sometimes ineffective). The quicklist approach doesn't have any easy way to return partial pages to general use. -Tony - To unsubscribe from this list: send the line "unsubscribe linux-ia64" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
