Re: Vacuum: allow usage of more than 1GB of work mem

On 04/06/2018 08:00 PM, Claudio Freire wrote:
> On Fri, Apr 6, 2018 at 5:25 PM, Claudio Freire <klaussfreire@gmail.com> wrote:
>> On Fri, Apr 6, 2018 at 10:39 AM, Heikki Linnakangas <hlinnaka@iki.fi> wrote:
>>> On 06/04/18 01:59, Claudio Freire wrote:
>>>> The iteration interface, however, seems quite specific for the use
>>>> case of vacuumlazy, so it's not really a good abstraction.
>>>
>>> Can you elaborate? It does return the items one block at a time. Is that
>>> what you mean by being specific for vacuumlazy? I guess that's a bit
>>> special, but if you imagine some other users for this abstraction, it's
>>> probably not that unusual. For example, if we started using it in bitmap
>>> heap scans, a bitmap heap scan would also want to get the TIDs one block
>>> number at a time.
>> But you're also tying the caller to the format of the buffer holding
>> those TIDs, for instance. Why would you, when you can have an
>> interface that just iterates TIDs and let the caller store them
>> if/however they want?
>>
>> I do believe a pure iterator interface is a better interface.
> Between the b-tree or not discussion and the refactoring to separate
> the code, I don't think we'll get this in the next 24hs.
>
> So I guess we'll have ample time to poner on both issues during the
> next commit fest.
>



There doesn't seem to have been much pondering done since then, at least 
publicly. Can we make some progress on this? It's been around for a long 
time now.

cheers

andrew

-- 
Andrew Dunstan                https://www.2ndQuadrant.com
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