Re: Server crash on RHEL 9/s390x platform against PG16

Hi,

On 2023-09-12 15:27:21 +0530, Suraj Kharage wrote:
> *[edb(at)9428da9d2137 postgres]$ cat /etc/redhat-release AlmaLinux release 9.2
> (Turquoise Kodkod)[edb(at)9428da9d2137 postgres]$ lscpuArchitecture:
> s390x CPU op-mode(s): 32-bit, 64-bit Address sizes: 39 bits

Can you provide the rest of the lscpu output? There have been issues with Z14
vs Z15:
https://github.com/llvm/llvm-project/issues/53009

You're apparently not hitting that, but given that fact, you either are on a
slightly older CPU, or you have applied a patch to work around it. Because
otherwise your uild instructions below would hit that problem, I think.

> physical, 48 bits virtual Byte Order: Big Endian*
> *Configure command:*
> ./configure --prefix=/home/edb/postgres/ --with-lz4 --with-zstd --with-llvm
> --with-perl --with-python --with-tcl --with-openssl --enable-nls
> --with-libxml --with-libxslt --with-systemd --with-libcurl --without-icu
> --enable-debug --enable-cassert --with-pgport=5414

Hm, based on "--with-libcurl" this isn't upstream postgres, correct? Have you
verified the issue reproduces on upstream postgres?

>
> *Test case:*
> CREATE TABLE rm32044_t1
> (
> pkey integer,
> val text
> );
> CREATE TABLE rm32044_t2
> (
> pkey integer,
> label text,
> hidden boolean
> );
> CREATE TABLE rm32044_t3
> (
> pkey integer,
> val integer
> );
> CREATE TABLE rm32044_t4
> (
> pkey integer
> );
> insert into rm32044_t1 values ( 1 , 'row1');
> insert into rm32044_t1 values ( 2 , 'row2');
> insert into rm32044_t2 values ( 1 , 'hidden', true);
> insert into rm32044_t2 values ( 2 , 'visible', false);
> insert into rm32044_t3 values (1 , 1);
> insert into rm32044_t3 values (2 , 1);
>
> postgres=# SELECT * FROM rm32044_t1 LEFT JOIN rm32044_t2 ON rm32044_t1.pkey
> = rm32044_t2.pkey, rm32044_t3 LEFT JOIN rm32044_t4 ON rm32044_t3.pkey =
> rm32044_t4.pkey order by rm32044_t1.pkey,label,hidden;

> server closed the connection unexpectedly
> This probably means the server terminated abnormally
> before or while processing the request.
> The connection to the server was lost. Attempting reset: Failed.
> The connection to the server was lost. Attempting reset: Failed.

I tried this on both master and 16, without hitting this issue.

If you can reproduce the issue on upstream postgres, can you share more about
your configuration?

Greetings,

Andres Freund