Message-ID: <f4b80948-4f81-4db8-b7a7-662d3b58da4e@iki.fi>
Date: Thu, 14 Mar 2024 22:59:50 +0200
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Subject: Re: Parallel Bitmap Heap Scan reports per-worker stats in EXPLAIN
 ANALYZE
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To: Melanie Plageman <melanieplageman@gmail.com>
Cc: Tomas Vondra <tomas.vondra@enterprisedb.com>,
 Dilip Kumar <dilipbalaut@gmail.com>, David Geier <geidav.pg@gmail.com>,
 PostgreSQL Developers <pgsql-hackers@lists.postgresql.org>
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 <ab3b05d5-c736-41d9-be6c-f747775baa8e@iki.fi>
 <20240314200006.emadubnx5nukthhi@liskov>
From: Heikki Linnakangas <hlinnaka@iki.fi>
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On 14/03/2024 22:00, Melanie Plageman wrote:
> On Thu, Mar 14, 2024 at 05:30:30PM +0200, Heikki Linnakangas wrote:
>> typedef struct SharedBitmapHeapInstrumentation
>> {
>> 	int			num_workers;
>> 	BitmapHeapScanInstrumentation sinstrument[FLEXIBLE_ARRAY_MEMBER];
>> } SharedBitmapHeapInstrumentation;
>>
>> typedef struct BitmapHeapScanState
>> {
>> 	ScanState	ss;				/* its first field is NodeTag */
>> 	...
>> 	SharedBitmapHeapInstrumentation sinstrument;
>> } BitmapHeapScanState;
>>
>> that compiles, at least with my compiler, but I find it weird to have a
>> variable-length inner struct embedded in an outer struct like that.
> 
> In the attached patch, BitmapHeapScanState->sinstrument is a pointer,
> though. Or are you proposing the above as an alternative that you
> decided not to go with?

Right, the above is what I contemplated at first but decided it was a 
bad idea.

-- 
Heikki Linnakangas
Neon (https://neon.tech)