Re: Relation extension scalability

On Wed, Mar 23, 2016 at 2:52 PM, Petr Jelinek <petr@2ndquadrant.com> wrote:
>> Second, if the other backend extended the relation in
>> some other manner and did not extend the FSM, how does calling
>> RecordAndGetPageWithFreeSpace help?  As far as I can see,
>> GetPageWithFreeSpace and RecordAndGetPageWithFreeSpace are both just
>> searching the FSM, so if one is stymied the other will be too.  What
>> am I missing?
>>
>
> The RecordAndGetPageWithFreeSpace will extend FSM as it calls
> fsm_set_and_search which in turn calls fsm_readbuf with extend = true.

So how does that help?  If I'm reading this right, the new block will
be all zeroes which means no space available on any of those pages.

-- 
Robert Haas
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