On Mon, Sep 06, 2010 at 09:00:35AM +0800, KOSAKI Motohiro wrote: > > On Tue, Aug 31, 2010 at 03:48:25PM +0800, Wu Fengguang wrote: > > > > > The output format is quite different from /proc/vmstat. > > > > > Do we really need to "Node X", ":" and "times" decorations? > > > > > > > > Node X is based on the meminfo file but I agree it's redundant information. > > > > > > Thanks. In the same directory you can find a different style example > > > /sys/devices/system/node/node0/numastat :) If ever the file was named > > > vmstat! In the other hand, shall we put the numbers there? I'm confused.. > > > > With wider use of NUMA, I'm expecting more interests to put > > /proc/vmstat items into /sys/devices/system/node/node0/. > > I prefer to create /sys/devices/system/node/node0/zones/zone-DMA32/vmstat > because the VM is managing pages as per-zones. > but /sys/devices/system/node/node0/vmstat is also useful. Good points. > > What shall we do then? There are several possible options: > > - just put the /proc/vmstat items into nodeX/numastat > > - create nodeX/vmstat and make numastat a symlink to vmstat > > - create nodeX/vmstat and remove numastat in future > > > > Any suggestions? > > > I like 3rd option :) > In addition, I doubt we really need to remove numastat. It's not > so harmful. Yeah 4th option: keep numastat while introducing the above interfaces. The contents might be duplicated, but not a big issue. > > > > > > > And the "_PAGES" in NR_FILE_PAGES_DIRTIED looks redundant to > > > > > the "_page" in node_page_state(). It's a bit long to be a pleasant > > > > > name. NR_FILE_DIRTIED/NR_CLEANED looks nicer. > > > > > > > > Yeah. Will fix. > > > > > > Thanks. This is kind of nitpick, however here is another name by > > > Jan Kara: BDI_WRITTEN. BDI_WRITTEN may not be a lot better than > > > BDI_CLEANED, but here is a patch based on Jan's code. I'm cooking > > > more patches that make use of this per-bdi counter to estimate the > > > bdi's write bandwidth, and to further decide the optimal (large) > > > writeback chunk size as well as to do IO-less balance_dirty_pages(). > > > > > > Basically BDI_WRITTEN and NR_CLEANED are accounting for the same > > > thing in different dimensions. So it would be good if we can use > > > the same naming scheme to avoid confusing users: either to use > > > BDI_WRITTEN and NR_WRITTEN, or use BDI_CLEANED and NR_CLEANED. > > > What's your opinion? > > > > I tend to prefer *_WRITTEN now. > > - *_WRITTEN reminds the users about IO, *_CLEANED is less so obvious. > > - *_CLEANED seems to be paired with NR_DIRTIED, this could be > > misleading to the users. The fact is, dirty pages may either be > > written to disk, or dropped (by truncate). > > Umm... > If my understanding is correct, Michael really need *_CLEANED because > he want to compare NR_DIRTIED and *_CLEANED. That said, we need to > change counter implementation itself instead a name? It's only about naming :) Michael want to do per-zone accounting and I also need to do per-bdi accounting, for basically the same event. So I'm proposing to name it consistently. Thanks, Fengguang -- 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/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>