Re: Report: Linux huge pages with Postgres

Simon Riggs <simon@2ndQuadrant.com> writes:
> On Sat, 2010-11-27 at 14:27 -0500, Tom Lane wrote:
>> This is discouraging; it certainly doesn't make me want to expend the
>> effort to develop a production patch.

> Perhaps.

> Why do this only for shared memory?

There's no exposed API for causing a process's regular memory to become
hugepages.

> Surely the majority of memory
> accesses are to private memory, so being able to allocate private memory
> in a single huge page would be better for avoiding TLB cache misses.

It's not really about the number of memory accesses, it's about the
number of TLB entries needed.  Private memory is generally a lot smaller
than shared, in a tuned PG installation.
        regards, tom lane