[PATCH 1/5] inode: Make unused inode LRU per superblock

[Nick Piggin]

On Tue, May 25, 2010 at 06:53:04PM +1000, Dave Chinner wrote:
> From: Dave Chinner <dchinner at redhat.com>
> 
> The inode unused list is currently a global LRU. This does not match
> the other global filesystem cache - the dentry cache - which uses
> per-superblock LRU lists. Hence we have related filesystem object
> types using different LRU reclaimatin schemes.

Is this an improvement I wonder? The dcache is using per sb lists
because it specifically requires sb traversal.

What allocation/reclaim really wants (for good scalability and NUMA
characteristics) is per-zone lists for these things. It's easy to
convert a single list into per-zone lists.

It is much harder to convert per-sb lists into per-sb x per-zone lists.