On Tue, Apr 26, 2011 at 04:50:49PM +0200, Peter Zijlstra wrote: > On Tue, 2011-04-26 at 15:46 +0100, Mel Gorman wrote: > > > > I did find that only a few route-cache entries should be required. In > > the original patches I worked with, there was a reservation for the > > maximum possible number of route-cache entries. I thought this was > > overkill and instead reserved 1-per-active-swapfile-backed-by-NFS. > > Right, so the thing I was worried about was a route-cache poison attack > where someone would spam the machine such that it would create a lot of > route cache entries and might flush the one we needed just as we needed > it. > > Pinning the one entry we need would solve that (if possible). That is a possibility all right, nice thoughts there. Ok, as I do not want this series to grow to the point where it is unreviewable, I'll mark pinning the routing cache entry for a follow-on series. In this series, the throttling logic should allow a new routing cache entry to be allocated by kswapd as it's immune to the throttle. Thanks. -- Mel Gorman SUSE Labs -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxxx For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>