The lockless page cache

I would be surprised if there was anything too noticeable for desktop types of workloads,
however 
the nice thing about these patches is that they actually speed up single threaded performance
as 
well as improve scalability.

Here is my justification to have them merged, which includes some numbers:
http://lwn.net/Articles/285339/

For server workloads using threads and direct IO, there should be some improvement at even 2
or 4 
cores. The OLTP database workload that gained nearly 10% throughput was run on a 2s/8c system,

so a 4 core system should see a few %.