On Wed, Dec 19, 2012 at 12:40:17PM +0400, Glauber Costa wrote: > The sysctl knob sysctl_vfs_cache_pressure is used to determine which > percentage of the shrinkable objects in our cache we should actively try > to shrink. > > It works great in situations in which we have many objects (at least > more than 100), because the aproximation errors will be negligible. But > if this is not the case, specially when total_objects < 100, we may end > up concluding that we have no objects at all (total / 100 = 0, if total > < 100). > > This is certainly not the biggest killer in the world, but may matter in > very low kernel memory situations. > > Signed-off-by: Glauber Costa <glommer@xxxxxxxxxxxxx> > CC: Dave Chinner <david@xxxxxxxxxxxxx> > CC: "Theodore Ts'o" <tytso@xxxxxxx> > CC: Al Viro <viro@xxxxxxxxxxxxxxxxxx> > --- > fs/super.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/fs/super.c b/fs/super.c > index 12f1237..660552c 100644 > --- a/fs/super.c > +++ b/fs/super.c > @@ -104,7 +104,7 @@ static int prune_super(struct shrinker *shrink, struct shrink_control *sc) > sb->s_nr_inodes_unused + fs_objects; > } > > - total_objects = (total_objects / 100) * sysctl_vfs_cache_pressure; > + total_objects = mult_frac(total_objects, sysctl_vfs_cache_pressure, 100); > drop_super(sb); > return total_objects; Hi Glauber, sysctl_vfs_cache_pressure all over the place with exactly the same calculation. Can you fix all of them in one pass? 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>