Re: Parallel Foreign Scans - need advice - Mailing list pgsql-hackers

From Korry Douglas
Subject Re: Parallel Foreign Scans - need advice
Date
Msg-id 0CC4C22A-AFA6-4045-B7D5-ADA222D5C098@me.com
Whole thread Raw
In response to Re: Parallel Foreign Scans - need advice  (Andres Freund <andres@anarazel.de>)
Responses Re: Parallel Foreign Scans - need advice  (Thomas Munro <thomas.munro@gmail.com>)
List pgsql-hackers
>> But, nworkers_launched is always set to 0 in
>> InitializeDSMForeignScan(), so that won’t work.  Any other ideas?
>
> At that state it's simply not yet known how many workers will be
> actually launched (they might not start successfully or such). Why do
> you need to know it there and not later?
>
> - Andres

I need to know at some point *before* I actually start scanning.  The ParallelContext pointer is only available in
EstimateDSMForeignScan(),InitializeDSMForeignScan(), and ReInitializeDSMForeignScan().   

If there is some other way to discover the actual worker count, I’m open to that.  The three functions above are not
particularlyhelpful to me so I’m happy to look somewhere else. 

         — Korry


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