Hi, On 2021-05-07 00:30:13 +0800, 盏一 wrote: > Since we have introduced `pgxactoff` in > [941697c3c1ae5d6ee153065adb96e1e63ee11224](https://github.com/postgres/postgres/commit/941697c3c1ae5d6ee153065adb96e1e63ee11224), > and `pgxactoff` is always the index of `proc->pgprocno` in > `procArray->pgprocnos`. So it seems that we could directly use > `proc->pgxactoff` as the value of `index` in `ProcArrayRemove()`? My thought > is to replace > > ```c > for (index = 0; index < arrayP->numProcs; index++) > { > if (arrayP->pgprocnos[index] == proc->pgprocno) > { > /* ... */ > } > } > ``` > > with > > ```c > index = proc->pgxactoff; > /* ... */ > ```
Sounds like a plan! Do you want to write a patch? If you do, I think it might be worthwhile to add an only-with-assertions loop checking that there's no other entry with the same pgprocno in the dense arrays. Given that the code is new in 14, I wonder if we should cram this simplification in before beta? I don't think this is likely to matter performance wise, but it seems like it'll make maintenance easier to not have it look different in 14 than it does both in 13 and 15. Greetings, Andres Freund
