Hi Simon, Try run "sync" before doing fadvise, because fadvise won't drop dirty/writeback/mapped pages. Thanks, Fengguang On Wed, Jan 09, 2013 at 02:05:21AM -0600, Simon Jeons wrote: > In attanchment. > root@kernel:~/Documents/mm/tools/linux-ftools# dd if=../../../images/ubuntu-11.04-desktop-i386.iso of=/tmpfs > 1403484+0 records in > 1403484+0 records out > 718583808 bytes (719 MB) copied, 19.5054 s, 36.8 MB/s > root@kernel:~/Documents/mm/tools/linux-ftools# ./linux-fincore -s ../../../images/ubuntu-11.04-desktop-i386.iso > filename size total_pages min_cached page cached_pages cached_size cached_perc > -------- ---- ----------- --------------- ------------ ----------- ----------- > ../../../images/ubuntu-11.04-desktop-i386.iso 718583808 175436 0 175436 718585856 100.00 > --- > total cached size: 718585856 > root@kernel:~/Documents/mm/tools/linux-ftools# ./linux-fadvise ../../../images/ubuntu-11.04-desktop-i386.iso DONTNEED 0,718585856 > Going to fadvise ../../../images/ubuntu-11.04-desktop-i386.iso as mode DONTNEED > offset: 0 > length: 718583808 > Invalid mode DONTNEED > root@kernel:~/Documents/mm/tools/linux-ftools# ./linux-fincore -s ../../../images/ubuntu-11.04-desktop-i386.iso > filename size total_pages min_cached page cached_pages cached_size cached_perc > -------- ---- ----------- --------------- ------------ ----------- ----------- > ../../../images/ubuntu-11.04-desktop-i386.iso 718583808 175436 0 175436 718585856 100.00 > --- > total cached size: 718585856 > -- 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>