Re: [reiserfs-dev] Re: Ext2 directory index: ALS paper and benchmarks

[Andrew Morton]

Daniel Phillips wrote:
> 
> Because Ext2 packs multiple entries onto a single inode table block, the
> major effect is not due to lack of readahead but to partially processed inode
> table blocks being evicted.

Inode and directory lookups are satisfied direct from the icache/dcache,
and the underlying fs is not informed of a lookup, which confuses the VM.

Possibly, implementing a d_revalidate() method which touches the
underlying block/page when a lookup occurs would help.

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