On 2016/5/13 15:00, Aaron Lu wrote: > On 05/13/2016 11:58 AM, Xishi Qiu wrote: >> I find the count nr_file_pages is not equal to nr_inactive_file + nr_active_file. >> There are 8 cpus, 2 zones in my system. >> >> I think may be the pagevec trigger the problem, but PAGEVEC_SIZE is only 14. >> Does anyone know the reason? > > One thing I can see is the ram backed filesystem where the page is > counted as NR_FILE_PAGE but go into the anonymous LRU list instead of > the file LRU list. > > See function shmem_getpage_gfp. > > An example: > [aaron@aaronlu ~]$ head -11 /proc/vmstat > nr_free_pages 194472 > nr_alloc_batch 58 > nr_inactive_anon 483386 > nr_active_anon 298161 > nr_inactive_file 452791 > nr_active_file 1942376 > nr_unevictable 84 > nr_mlock 84 > nr_anon_pages 445332 > nr_mapped 93553 > nr_file_pages 2731481 > [aaron@aaronlu ~]$ fallocate -l 400M /dev/shm/test > [aaron@aaronlu ~]$ head -11 /proc/vmstat > nr_free_pages 94808 > nr_alloc_batch 838 > nr_inactive_anon 582385 > nr_active_anon 298371 > nr_inactive_file 452795 > nr_active_file 1942380 > nr_unevictable 84 > nr_mlock 84 > nr_anon_pages 445543 > nr_mapped 93658 > nr_file_pages 2830488 > > The nr_file_pages increased with nr_inactive_anon while the > nr_{in}active_file don't see much change. > > Regards, > Aaron > Hi Aaron, Thanks for your reply, but I find the count of nr_shmem is very small in my system. root@hi3650:/ # cat /proc/vmstat nr_free_pages 54192 nr_inactive_anon 39830 nr_active_anon 28794 nr_inactive_file 432444 nr_active_file 20659 nr_unevictable 2363 nr_mlock 0 nr_anon_pages 65249 nr_mapped 19742 nr_file_pages 462723 nr_dirty 20 nr_writeback 0 nr_slab_reclaimable 259333 nr_slab_unreclaimable 33463 nr_page_table_pages 3456 nr_kernel_stack 892 nr_unstable 0 nr_bounce 11 nr_vmscan_write 292032 nr_vmscan_immediate_reclaim 47204474 nr_writeback_temp 0 nr_isolated_anon 0 nr_isolated_file 0 nr_shmem 128 nr_dirtied 69574 nr_written 356299 nr_anon_transparent_hugepages 0 nr_free_cma 7519 nr_swapcache 41972 nr_dirty_threshold 6982 nr_dirty_background_threshold 99297 -- 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/ . Don't email: <a href=mailto:"dont@xxxxxxxxx"> email@xxxxxxxxx </a>