On Wednesday 22 June 2011 08:35:36 Chris Wright wrote: > * Nai Xia (nai.xia@xxxxxxxxx) wrote: > > (Sorry for repeated mail, I forgot to Cc the list..) > > > > On Wednesday 22 June 2011 06:38:00 you wrote: > > > * Nai Xia (nai.xia@xxxxxxxxx) wrote: > > > > Introduced ksm_page_changed() to reference the dirty bit of a pte. We clear > > > > the dirty bit for each pte scanned but don't flush the tlb. For a huge page, > > > > if one of the subpage has changed, we try to skip the whole huge page > > > > assuming(this is true by now) that ksmd linearly scans the address space. > > > > > > This doesn't build w/ kvm as a module. > > > > I think it's because of the name-error of a related kvm patch, which I only sent > > in a same email thread. http://marc.info/?l=linux-mm&m=130866318804277&w=2 > > The patch split is not clean...I'll redo it. > > > > It needs an export as it is. > ERROR: "kvm_dirty_update" [arch/x86/kvm/kvm-intel.ko] undefined! Oops, yes, I forgot to do that! I'll correct it in the next submission. Thanks, Nai > > Although perhaps could be done w/out that dirty_update altogether (as I > mentioned in other email)? > > > > > > > > A NEW_FLAG is also introduced as a status of rmap_item to make ksmd scan > > > > more aggressively for new VMAs - only skip the pages considered to be volatile > > > > by the dirty bits. This can be enabled/disabled through KSM's sysfs interface. > > > > > > This seems like it should be separated out. And while it might be useful > > > to enable/disable for testing, I don't think it's worth supporting for > > > the long term. Would also be useful to see the value of this flag. > > > > I think it maybe useful for uses who want to turn on/off this scan policy explicitly > > according to their working sets? > > Can you split it out, and show the benefit of it directly? I think it > only benefits: > > p = mmap() > memset(p, $value, entire buffer); > ... > very slowly (w.r.t scan times) touch bits of buffer and trigger cow to > break sharing. > > Would you agree? > > thanks, > -chris > -- 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>