Hi, On Wed, Jun 29, 2011 at 01:11:00PM -0700, Andi Kleen wrote: > Dave Hansen <dave@xxxxxxxxxxxxxxxxxx> writes: > > > > It's also going to be a pain to track kernel references. On x86, our > As Vaidy mentioned, we are only looking at memory being either allocated or free, as a way to evacuate it. Tracking memory references, no doubt, is a difficult proposition and might involve a lot of overhead. > Even if you tracked them what would you do with them? > > It's quite hard to stop using arbitary kernel memory (see all the dancing > memory-failure does) > > You need to track the direct accesses to user data which happens > to be accessed through the direct mapping. > > Also it will be always unreliable because this all won't track DMA. > For that you would also need to track in the dma_* infrastructure, > which will likely get seriously expensive. > -- Regards, Ankita Garg (ankita@xxxxxxxxxx) Linux Technology Center IBM India Systems & Technology Labs, Bangalore, India -- 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>