Hey, On Wed, Apr 20, 2011 at 08:50:15AM -0500, Christoph Lameter wrote: > Tejon was working on getting rid of DISCONTIG. SPARSEMEM is the favored > alternative today. So we could potentially change the arches to use SPARSE > configs in the !NUMA case. Well, the thing is that sparsemem w/ vmemmap is definitely better than discontigmem on x86-64; however, on x86-32, vmemmap can't be used due to address space shortage and there are some minor disadvantages to sparsemem compared to discontigmem. IIRC, the biggest was losing a bit of granuality in memsections and possibly wasting slightly more memory on the page array. Both didn't seem critical to me but given that the actual amount of code needed for discontigmem in arch code was fairly small (although the amount of added complexity for auditing/testing can be much higher) I didn't feel sure about dropping discontigmem and thus the patchset to drop discontigmem was posted as RFC, to which nobody commented. http://thread.gmane.org/gmane.linux.kernel/1121321 What do you guys think? Thanks. -- tejun -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxxx 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>