Thread: Re: BUG #17072: Assert for clogGroupNext failed due to a race condition in TransactionGroupUpdateXidStatus()
Re: BUG #17072: Assert for clogGroupNext failed due to a race condition in TransactionGroupUpdateXidStatus()
From
Alexander Lakhin
Date:
24.06.2021 19:00, PG Bug reporting form wrote: > With some diagnostic output added I've got in the server log: The diagnostic patch is attached. I could not find an easy reproduction for the issue, so I can propose only dirty one, with the special debug patch and the following script: for i in `seq 100`; do createdb db$i done echo " CREATE TABLE tst (i INT); INSERT INTO tst SELECT i FROM generate_series(1,100) i; DROP TABLE tst; " >/tmp/action.sql for n in `seq 100`; do echo "iteration $n" for i in `seq 100`; do ( { for f in `seq 10`; do cat /tmp/action.sql; done } | psql -d db$i ) >psql-$i.log 2>&1 & done wait coredumpctl --no-pager && break done (You need to set max_connections = 100 in postgresql.conf.) This script with the patched server fails for me on iterations 66, 12, 12. Best regards, Alexander
Attachment
Re: BUG #17072: Assert for clogGroupNext failed due to a race condition in TransactionGroupUpdateXidStatus()
From
vignesh C
Date:
On Thu, Jun 24, 2021 at 9:45 PM Alexander Lakhin <exclusion@gmail.com> wrote: > > 24.06.2021 19:00, PG Bug reporting form wrote: > > With some diagnostic output added I've got in the server log: > The diagnostic patch is attached. > > I could not find an easy reproduction for the issue, so I can propose > only dirty one, with the special debug patch and the following script: > > for i in `seq 100`; do > createdb db$i > done > > echo " > CREATE TABLE tst (i INT); > INSERT INTO tst SELECT i FROM generate_series(1,100) i; > DROP TABLE tst; > " >/tmp/action.sql > > for n in `seq 100`; do > echo "iteration $n" > for i in `seq 100`; do > ( { for f in `seq 10`; do cat /tmp/action.sql; done } | psql -d db$i > ) >psql-$i.log 2>&1 & > done > wait > coredumpctl --no-pager && break > done > > (You need to set max_connections = 100 in postgresql.conf.) > This script with the patched server fails for me on iterations 66, 12, 12. I was not able to reproduce the problem with REL_13_3, REL_13_Stable & Head branch with the script and patch shared. I will check and see if I can reproduce the problem with the new script that you have shared. Regards, Vignesh