Sergei Golubchik wrote:
> Hi, Mikiya!
>
> On May 18, Mikiya Okuno wrote:
>> Hi,
>>
>> Does this include a large pages support?
>
> No, it does not.
> May be later.
>
>> I encountered a problem that the performance went down when several
>> mega bytes were assigned for each read buffer, read rnd buffer and
>> sort buffer on a Nocona system. I suspect that many TLB cache miss
>> were happening at that time. Currently, MySQL only supports large
>> pages for InnoDB. If MySQL will have a slab allocator which supports
>> large pages like memcached, the performance will improve due to less
>> TLB cache miss, won't it?
>
> large pages are used for myisam keycache, that's why the support for
> them was added in the first place.
>
> There's no problem to use them elsewhere, where it make sense.
>
> But there aren't many places where it make sense, as, indeed, we don't
> have a generic purpose allocator in the server.
It could be pretty low-hanging to organize all memroots within the
server below a global mmap'ed allocator.
Thanks,
Roy
