On 02/23/2013 07:37 PM, Phillip Susi wrote: > This is the correct behavior prescribed by posix. If you have been > using it for that purpose in the past, then you were using the wrong > syscall. If you want to begin writeout now, then you should be using > sync_file_range(). As it was, it only initiated writeout if the > backing device was not already congested, which is going to no longer > be the case rather soon if you ( or other tasks ) are writing > significant amounts of data. > > If you really want to stay out of memory reclaim entirely, then you > should be using O_DIRECT. These are folks that want to use the page cache, but also want to be in control of when it gets written out (sync_file_range() is used) and when it goes away. Sure, they can use O_DIRECT and do all of the buffering internally, but that means changing the application. I actually really like the concept behind your patch. It looks like very useful functionality. I'm just saying that I know it will break _existing_ users. I'm actually in the process of _trying_ to extricate this particular app from handling their own reclaim management entirely. Your patch looks like a nice part of the puzzle. -- 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>