Re: SUBTRANS: Minimizing calls to SubTransSetParent()

On 11/17/22 18:29, Simon Riggs wrote:
> On Thu, 17 Nov 2022 at 17:04, Simon Riggs <simon(dot)riggs(at)enterprisedb(dot)com> wrote:
>>
>> New version with greatly improved comments coming very soon.
>
>>> Perhaps it would be a good idea to split up the patch. The business
>>> about making pg_subtrans flat rather than a tree seems like a good
>>> idea in any event, although as I said it doesn't seem like we've got
>>> a fleshed-out version of that here. We could push forward on getting
>>> that done and then separately consider the rest of it.
>>
>> Yes, I thought you might ask that so, after some thought, have found a
>> clean way to do that and have split this into two parts.
>
> Attached.
>
> 002 includes many comment revisions, as well as flattening the loops
> in SubTransGetTopmostTransaction and TransactionIdDidCommit/Abort
> 003 includes the idea to not-always do SubTransSetParent()
>

I'm a bit confused by the TransactionIdsAreOnSameXactPage naming. Isn't
this really checking clog pages?

regards

--
Tomas Vondra
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