Re: Remove redundant MemoryContextSwith in BeginCopyFrom - Mailing list pgsql-hackers

From Japin Li
Subject Re: Remove redundant MemoryContextSwith in BeginCopyFrom
Date
Msg-id MEYP282MB166965E690F6C58F85BE0B69B65A9@MEYP282MB1669.AUSP282.PROD.OUTLOOK.COM
Whole thread Raw
In response to Re: Remove redundant MemoryContextSwith in BeginCopyFrom  (Tom Lane <tgl@sss.pgh.pa.us>)
Responses Re: Remove redundant MemoryContextSwith in BeginCopyFrom
List pgsql-hackers
On Thu, 20 Jan 2022 at 00:38, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com> writes:
>> +1. It looks like a thinko from c532d15d. There's no code in between,
>> so switching to oldcontext doesn't make sense.
>
> Agreed.
>
>> I think we also need to remove MemoryContextSwitchTo(oldcontext); at
>> the end of BeginCopyTo in copyto.c, because we are not changing memory
>> contexts in between.
>
> Hmm, I think it'd be a better idea to remove the one in the middle of
> BeginCopyTo.  The code after that is still doing setup of the cstate,
> so the early switch back looks to me like trouble waiting to happen.
>

Agreed

I see you have already push this patch on master (89f059bdf52), why not
remove MemoryContextSwitchTo in the middle of BeginCopyTo in this commit?

-- 
Regrads,
Japin Li.
ChengDu WenWu Information Technology Co.,Ltd.



pgsql-hackers by date:

Previous
From: "Bossart, Nathan"
Date:
Subject: Re: Add checkpoint and redo LSN to LogCheckpointEnd log message
Next
From: Tom Lane
Date:
Subject: Re: Remove redundant MemoryContextSwith in BeginCopyFrom