Re: Re: Optimize SnapBuildPurgeOlderTxn: use in-place compaction instead of temporary array

[Xuneng Zhou]

Hi Dewei,

On Thu, Jan 8, 2026 at 6:42 PM Dewei Dai <daidewei1...@163.com> wrote:
>
> Hi Xuneng,
>
> On Thu, Jan 8, 2026 at 4:15 PM Xuneng Zhou <xunengzhou(at)gmail(dot)com> 
> wrote:
> >
> > v3-0001 fixes a critical issue where the snapshot->xip array in
> > SnapBuildBuildSnapshot might not be sorted before reaching the
> > consistent state. Sorry for the noise here.
> >
> >
>  I just reviewed the v3 and I got a few comment
> in function `SnapBuildAddCommittedTxns`
> `builder->committed.xcnt_space = builder->committed.xcnt_space * 2 + 1`
>
> Wouldn't it be more appropriate to use:
> `builder->committed.cnt_space = builder->committed.xcnt_space * 2`
>
>
> Best regards，
>

Thanks for looking into this.

Yeah, we don't need the +1 in the while loop. I'll remove it.



--
Best,
Xuneng