From: | "Pavan Deolasee" <pavan(dot)deolasee(at)gmail(dot)com> |
---|---|
To: | "Heikki Linnakangas" <heikki(at)enterprisedb(dot)com> |
Cc: | pgsql-patches(at)postgresql(dot)org |
Subject: | Re: HOT Patch - Ready for review |
Date: | 2007-04-20 07:57:26 |
Message-ID: | 2e78013d0704200057q331fcbc7p4ea96eba42bd79a1@mail.gmail.com |
Views: | Raw Message | Whole Thread | Download mbox | Resend email |
Thread: | |
Lists: | pgsql-patches |
On 4/19/07, Heikki Linnakangas <heikki(at)enterprisedb(dot)com> wrote:
>
>
> What's the purpose of the "HeapScanHintPagePrune" mechanism in index
> builds? I lost track of the discussion on create index, is the it
> necessary for correctness?
Its not required strictly for correctness, but it helps us prune the
HOT-chains
while index building. During index build, if we skip a tuple which is
RECENTLY_DEAD, existing transactions can not use the index for queries.
Pruning the HOT-chains reduces the possibility of finding such tuples
while building the index.
A comment in IndexBuildHeapScan explaining
> why it's done would be nice.
I would do that.
In any case a PG_TRY/CATCH block should be
> used to make sure it's turned off after an unsuccessful index build.
Oh thanks. Would do that too
I would wait for other review comments before submitting a fresh patch.
I hope thats ok.
Thanks,
Pavan
--
EnterpriseDB http://www.enterprisedb.com
From | Date | Subject | |
---|---|---|---|
Next Message | Zeugswetter Andreas ADI SD | 2007-04-20 08:16:15 | Re: [HACKERS] Full page writes improvement, code update |
Previous Message | Pavel Stehule | 2007-04-20 07:46:28 | actualised forgotten Magnus's patch for plpgsql MOVE statement |