On Tue, Feb 16, 2016 at 02:58:04AM +0000, Nag Avadhanam (nag) wrote: > Its the calculation of the # of bytes of non-reclaimable file system cache > pages that has been troubling us. We do not want to count inactive file > pages (of programs/binaries) that were once mapped by any process in the > system as reclaimable because that might lead to thrashing under memory > pressure (we want to alert admins before system starts dropping text > pages). The code presented does not match your requirements. It only counts pages that are currently mapped into ptes. hence it will tell you that once-used and now unmapped binary pages are reclaimable, and drop caches will reclaim them. hence they'll need to be fetched from disk again if they are faulted in again after a drop_caches run. Cheers, Dave. -- Dave Chinner david@xxxxxxxxxxxxx -- 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>