On Tue, 25 May 2010 18:53:03 +1000 Dave Chinner <david@xxxxxxxxxxxxx> wrote: > This series reworks the filesystem shrinkers. We currently have a > set of issues with the current filesystem shrinkers: > > 1. There is an dependency between dentry and inode cache > shrinking that is only implicitly defined by the order of > shrinker registration. > 2. The shrinkers need to walk the superblock list and pin > the superblock to avoid unmount races with the sb going > away. > 3. The dentry cache uses per-superblock LRUs and proportions > reclaim between all the superblocks which means we are > doing breadth based reclaim. This means we touch every > superblock for every shrinker call, and may only reclaim > a single dentry at a time from a given superblock. > 4. The inode cache has a global LRU, so it has different > reclaim patterns to the dentry cache, despite the fact > that the dentry cache is generally the only thing that > pins inodes in memory. > 5. Filesystems need to register their own shrinkers for > caches and can't co-ordinate them with the dentry and > inode cache shrinkers. Nice description, but... it never actually told us what the benefit of the changes are. Presumably some undescribed workload had some undescribed user-visible problem. But what was that workload, and what was the user-visible problem, and how does the patch affect all this? Stuff like that. -- 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/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>