Re: Relation extension scalability

On Sat, Jan 23, 2016 at 12:19 PM, Amit Kapila <amit(dot)kapila16(at)gmail(dot)com>
wrote:

> On Tue, Jan 12, 2016 at 2:41 PM, Dilip Kumar <dilipbalaut(at)gmail(dot)com>
> wrote:
>
>> On Thu, Jan 7, 2016 at 4:53 PM, Andres Freund <andres(at)anarazel(dot)de> wrote:
>>
>>> On 2016-01-07 16:48:53 +0530, Amit Kapila wrote:
>>>
>>> I think it's a worthwhile approach to pursue. But until it actually
>>> fixes the problem of leaving around uninitialized pages I don't think
>>> it's very meaningful to do performance comparisons.
>>>
>>
>> Attached patch solves this issue, I am allocating the buffer for each
>> page and initializing the page, only after that adding to FSM.
>>
>
> Few comments about patch:
>
>
I found one more problem with patch.

! UnlockReleaseBuffer(buffer);
! RecordPageWithFreeSpace(relation, BufferGetBlockNumber(buffer),
freespace);

You can't call BufferGetBlockNumber(buffer) after releasing
the pin on buffer which will be released by
UnlockReleaseBuffer(). Get the block number before unlocking
the buffer.

With Regards,
Amit Kapila.
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