Re: Relation extension scalability

On Thu, Mar 24, 2016 at 10:44 AM, Robert Haas <robertmhaas(at)gmail(dot)com> wrote:

> On Wed, Mar 23, 2016 at 9:43 PM, Amit Kapila <amit(dot)kapila16(at)gmail(dot)com>
> wrote:
> > RecordAndGetPageWithFreeSpace() tries to search from the oldPage passed
> to
> > it, rather than from top, so even if RecordPageWithFreeSpace() doesn't
> > update till root, it will be able to search the newly added page. I
> agree
> > with whatever you have said in another mail that we should introduce a
> new
> > API to do a more targeted search for such cases.
>
> OK, let's do that, then.

Ok, I have added new API which just find the free block from and start
search from last given page.

1. I have named the new function as GetPageWithFreeSpaceUsingOldPage, I
don't like this name, but I could not come up with any better, Please
suggest one.

And also body of GetPageWithFreeSpaceUsingOldPage looks almost similar to
RecordAndGetPageWithFreeSpace, I tried to merge these two but for that we
need to pass extra parameter to the function.

2. I also had to write one more function *fsm_search_from_addr *instead of
using* fsm_set_and_search. *So that we can find block without updating the
other slot.

I have done performance test just to ensure the result. And performance is
same as old. with both COPY and INSERT.

3. I have also run pgbench read-write what amit suggested upthread.. No
regression or improvement with pgbench workload.

Client base Patch
1 899 914
8 5397 5413
32 18170 18052
64 29850 29941

--
Regards,
Dilip Kumar
EnterpriseDB: http://www.enterprisedb.com