Subject: Re: cleanup temporary files after crash
To: Euler Taveira <euler@eulerto.com>, Thomas Munro <thomas.munro@gmail.com>,
 Michael Paquier <michael@paquier.xyz>
Cc: Euler Taveira <euler.taveira@2ndquadrant.com>,
 Anastasia Lubennikova <a.lubennikova@postgrespro.ru>,
 Tomas Vondra <tomas.vondra@2ndquadrant.com>,
 PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>,
 Tom Lane <tgl@sss.pgh.pa.us>
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From: Tomas Vondra <tomas.vondra@enterprisedb.com>
Message-ID: <482a6498-7713-e937-c554-7d235c415fba@enterprisedb.com>
Date: Fri, 19 Mar 2021 02:21:29 +0100
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On 3/19/21 1:54 AM, Euler Taveira wrote:
> On Thu, Mar 18, 2021, at 8:34 PM, Tomas Vondra wrote:
>> Well, that's better, bit it still does not do the trick on the 32-bit
>> machine - in that case a 1000 rows with int4 still fit into work_mem, so
>> the temp file is not created. Per my experiments about 1040 rows are
>> needed - soooo close ;-) So let's make it 2000.
> My 32-bit laptop needs some repairs so I blindly chose 1k rows.
> 

Yeah, it's not immediately obvious how many rows are needed. 2000 would
be enough, but I just bumped it up to 5000 for good measure.

>> We might as well check that the temp file actually exists, before
>> killing the backend. Just to be sure.
> Do you mean with remove_temp_files_after_crash = on? New version attached.
> 

On second thought, we don't need that check. I realized the second part
of the test (checking remove_temp_files_after_crash=off) actually does
verify that we've created the file, so that should be OK.

I've pushed the previous version with the 5000 rows. Let's see what
crake and florican think about this ...


regards

-- 
Tomas Vondra
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