-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 I believe the current implementation for this is wrong. For clean pages, it immediately discards them from the cache, and for dirty ones, it immediately tries to initiate writeout if the bdi is not congested. I believe this is wrong for three reasons: 1) It is completely useless for writing files. This hint should allow a program generating lots of writes to files that will not likely be read again to reduce the cache pressure that causes. 2) When there is little to no cache pressure, this hint should not cause the disk to spin up. 3) This is supposed to be a hint that caching this data is unlikely to do any good, so the cache should favor other data instead. Just because one process does not think it will be used again does not mean it won't be, so when there is little to no cache pressure, we shouldn't go discarding potentially useful data. I'd like to change this to simply force the pages to the inactive list, so they will be reclaimed sooner than other pages, but not immediately discarded, or written out. Also the related POSIX_FADV_NOREUSE is currently unimplemented, and this should also cause the cache pages to skip the active list and go straight to the inactive list. Any thoughts or hints on how to go about doing this? -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.17 (MingW32) Comment: Using GnuPG with Thunderbird - http://www.enigmail.net/ iQEcBAEBAgAGBQJRJ82ZAAoJEJrBOlT6nu75i3YIAMjrwhzL28m/WbsD4m2BQaX9 swz0OlO9AimoQLE0vvbYSRYFmlGAayQafIOJU1GiLSijPGmHqisOePZpWnCKbesP PeoHFxC+jDNHGrmIDHGOgq7ELAX6DNh5yU1sBhvo7iSnDCfjdfvJP7wWNyzCD/bD FT7bEgQ1vjd6bB3812Qj3PBs/UHvHUj8zAJDAiArqMJSW6LgxINzjyXs030NRqxS A1RUVUJ/4ydJz7SS4uitFWmObrpImIt6oxpQnIb1SOzL67KNx/YwMgWq/hknAS3H ravePc2VwH2aS/gcyo2VW3OLHlIXOxgbjhZWbKidkNv6KsccEqqY8yFeO+fCvjA= =dsVO -----END PGP SIGNATURE----- -- 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>