On Tue, Aug 14, 2007 at 10:57:31AM +0530, Balbir Singh wrote: > I keep forgetting to check that you are on the cc. My email client > loves dropping you from the to/cc list.
hehe, sorry for my crappy smtp server ;) > Fengguang Wu wrote: > > The "proportional set size" (PSS) of a process is the count of pages it has > > in > > memory, where each page is divided by the number of processes sharing it. > > So if > > a process has 1000 pages all to itself, and 1000 shared with one other > > process, > > its PSS will be 1500. > > - lwn.net: "ELC: How much memory are applications really > > using?" > > > > The PSS proposed by Matt Mackall is a very nice metic for measuring an > > process's > > memory footprint. So collect and export it via /proc/<pid>/smaps. > > > > Matt Mackall's pagemap/kpagemap and John Berthels's exmap can also do the > > job, > > providing pretty much details. But for PSS, let's do it in a simple way. > > > > Cc: Matt Mackall <[EMAIL PROTECTED]> > > Cc: John Berthels <[EMAIL PROTECTED]> > > Signed-off-by: Fengguang Wu <[EMAIL PROTECTED]> > > I like the idea of moving towards PSS. I had sent some patches back in > December > last year > > http://marc.info/?l=linux-mm&m=116738715329816&w=4 Thank you. That's a pretty comprehensive work. > > - if (page_mapcount(page) >= 2) { > > + mapcount = page_mapcount(page); > > + if (mapcount >= 2) { > > This accounting is of-course racy. Mapcount can change any moment. Sure it is: I never expect to provide accurate numbers. The mapcount here is to prevent divide-by-zero errors. > If we are reasonably sure that mapping will not change at the time > of page_rmap_xxxxx() operations, we could handle shared accounting > at those points and implement accurate shared accounting. That would be desirable, if only we can keep the cost low ;) - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
