On Thursday 18 October 2007 17:14, Vasily Averin wrote: > Nick Piggin wrote: > > Hi, > > > > On Thursday 18 October 2007 16:24, Vasily Averin wrote: > >> Hi all, > >> > >> could anybody explain how "inactive" may be much greater than "cached"? > >> stress test (http://weather.ou.edu/~apw/projects/stress/) that writes > >> into removed files in cycle puts the node to the following state: > >> > >> MemTotal: 16401648 kB > >> MemFree: 636644 kB > >> Buffers: 1122556 kB > >> Cached: 362880 kB > >> SwapCached: 700 kB > >> Active: 1604180 kB > >> Inactive: 13609828 kB > >> > >> At the first glance memory should be freed on file closing, nobody > >> refers to file and ext3_delete_inode() truncates inode. We can see that > >> memory is go away from "cached", however could somebody explain why it > >> become "invalid" instead be freed? Who holds the references to these > >> pages? > > > > Buffers, swap cache, and anonymous. > > But buffers and swap cache are low (1.1 Gb and 700kB in this example) and > anonymous should go away when process finished. Ah, I didn't see it was an order of magnitude out. Some filesystems, including I believe, ext3 with data=ordered, can leave orphaned pages around after they have been truncated out of the pagecache. These pages get left on the LRU and vmscan reclaims them pretty easily. Try ext3 data=writeback, or even ext2. - To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
