Thread: BUG #16427: pgsql_tmp - temp files not released
The following bug has been logged on the website: Bug reference: 16427 Logged by: Murali Natti Email address: murali.natti@gmail.com PostgreSQL version: 10.5 Operating system: Red Hat Enterprise Linux Server release 6.10 (Sant Description: Hello Team, We have observed a bug ( I guess ) that temporary files were not deleted automatically even thought the respective PIDs are not running anymore. We couldn't take a chance to delete files manually so ended up with restarting database to clear temp files. Is this know bug, what could be the reason for this? Can anyone please let us know? Thanks, Murali
On Sun, May 10, 2020 at 12:44:18AM +0000, PG Bug reporting form wrote: >The following bug has been logged on the website: > >Bug reference: 16427 >Logged by: Murali Natti >Email address: murali.natti@gmail.com >PostgreSQL version: 10.5 >Operating system: Red Hat Enterprise Linux Server release 6.10 (Sant >Description: > >Hello Team, > >We have observed a bug ( I guess ) that temporary files were not deleted >automatically even thought the respective PIDs are not running anymore. > >We couldn't take a chance to delete files manually so ended up with >restarting database to clear temp files. > >Is this know bug, what could be the reason for this? Can anyone please let >us know? > I don't think we're aware of any live bug in this area (although you're a couple of minor releases behind, and I haven't checked release notes between 10.5 and 10.12). I think you need to investigate what happened to the backends/commands that created the temporary files. Presumably it was interrupted or terminated in a way that prevented proper cleanup. regards -- Tomas Vondra http://www.2ndQuadrant.com PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services
On Sun, 10 May 2020 at 09:32, Tomas Vondra <tomas.vondra@2ndquadrant.com> wrote:
On Sun, May 10, 2020 at 12:44:18AM +0000, PG Bug reporting form wrote:
>The following bug has been logged on the website:
>
>Bug reference: 16427
>Logged by: Murali Natti
>Email address: murali.natti@gmail.com
>PostgreSQL version: 10.5
>Operating system: Red Hat Enterprise Linux Server release 6.10 (Sant
>Description:
>
>Hello Team,
>
>We have observed a bug ( I guess ) that temporary files were not deleted
>automatically even thought the respective PIDs are not running anymore.
>
>We couldn't take a chance to delete files manually so ended up with
>restarting database to clear temp files.
>
>Is this know bug, what could be the reason for this? Can anyone please let
>us know?
>
I don't think we're aware of any live bug in this area (although you're
a couple of minor releases behind, and I haven't checked release notes
between 10.5 and 10.12).
I think you need to investigate what happened to the backends/commands
that created the temporary files. Presumably it was interrupted or
terminated in a way that prevented proper cleanup.
I bet OP has crash(es) while executing a query that uses temporary files.
Crash does not cleanup temporary files until you restart the service.
RemovePgTempFiles says:
Crash does not cleanup temporary files until you restart the service.
RemovePgTempFiles says:
* NOTE: we could, but don't, call this during a post-backend-crash restart
* cycle. The argument for not doing it is that someone might want to examine
* the temp files for debugging purposes. This does however mean that
* OpenTemporaryFile had better allow for collision with an existing temp
* file name.
* cycle. The argument for not doing it is that someone might want to examine
* the temp files for debugging purposes. This does however mean that
* OpenTemporaryFile had better allow for collision with an existing temp
* file name.
I wonder if a GUC (cleanup_temp_files_after_crash) is useful for an
environment that has storage restrictions. This is the second time this
month that I stumbled on this issue. Of course, I don't expect a postgres
crash once a while but we know that, due to extensibility, some extensions
could crash and the only workaround to this issue is to restart service
(which means a human intervention and an additional downtime).
--
environment that has storage restrictions. This is the second time this
month that I stumbled on this issue. Of course, I don't expect a postgres
crash once a while but we know that, due to extensibility, some extensions
could crash and the only workaround to this issue is to restart service
(which means a human intervention and an additional downtime).
Euler Taveira http://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services
On Sun, May 10, 2020 at 10:48:58AM -0300, Euler Taveira wrote: > I wonder if a GUC (cleanup_temp_files_after_crash) is useful for an > environment that has storage restrictions. This is the second time this > month that I stumbled on this issue. Of course, I don't expect a postgres > crash once a while but we know that, due to extensibility, some extensions > could crash and the only workaround to this issue is to restart service > (which means a human intervention and an additional downtime). Sounds like a fair concern to me. It is annoying to have to do some manual intervention for some environments under disk pressure. -- Michael
Attachment
It again happened today and this time it happened in PG11.4 DB. We had to bounce the instance to clear the space.
On Sun, May 10, 2020 at 11:10 PM Michael Paquier <michael@paquier.xyz> wrote:
On Sun, May 10, 2020 at 10:48:58AM -0300, Euler Taveira wrote:
> I wonder if a GUC (cleanup_temp_files_after_crash) is useful for an
> environment that has storage restrictions. This is the second time this
> month that I stumbled on this issue. Of course, I don't expect a postgres
> crash once a while but we know that, due to extensibility, some extensions
> could crash and the only workaround to this issue is to restart service
> (which means a human intervention and an additional downtime).
Sounds like a fair concern to me. It is annoying to have to do some
manual intervention for some environments under disk pressure.
--
Michael
Thanks,
Murali