Hi, OK I think I have something concrete - running hammer rebalance on a freshly booted machine runs the active memory usage up past 2GB and it stays there after the rebalance has finished even when the machine is left alone for some time.
Unmounting and remounting the filesystem clears up the memory usage but nothing else seems to do it. I can understand that operations like this will bring a lot of blocks into memory and it probably helps performance on systems with high filesystem activity to keep them in but surely they shouldn't stay on the active queue, where the memory cannot be reused, indefinitely. Shuffling them off to the inactive queue once they are written out (or just not dirty) would enable the blocks to be reused and seems to make more sense to me. -- Steve O'Hara-Smith | Directable Mirror Arrays C:>WIN | A better way to focus the sun The computer obeys and wins. | licences available see You lose and Bill collects. | http://www.sohara.org/