pg_dump: error: schema with OID 7956828 does not exist

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pg_dump: error: schema with OID 7956828 does not exist

nemo
Hello, I have a problem on PG12
os:CentOS Linux release 7.4.1708 (Core)
db:PostgreSQL 12.0

the db log is
2019-11-08 11:59:40.385 CST,,,19005,,5dc4e7d2.4a3d,1,,2019-11-08 11:58:10
CST,1/0,0,WARNING,57P02,"terminating connection because of crash of another
server process","The postmaster has commanded this server process to roll
back the current transaction and exit, because another server process exited
abnormally and possibly corrupted shared memory.","In a moment you should be
able to reconnect to the database and repeat your command.",,,,,,"quickdie,
postgres.c:2717","

os message ,i find is not oom
Nov  6 10:00:02 xx-xx crond: /usr/sbin/sendmail: Cannot allocate memory
Nov  8 16:23:59 xx-xx kernel: Reserving 161MB of memory at 688MB for
crashkernel (System RAM: 8191MB)
Nov  8 16:23:59 xx-xx kernel: Early memory node ranges
Nov  8 16:23:59 xx-xx kernel: PM: Registered nosave memory: [mem
0x0009f000-0x0009ffff]
Nov  8 16:23:59 xx-xx kernel: PM: Registered nosave memory: [mem
0x000a0000-0x000effff]
Nov  8 16:23:59 xx-xx kernel: PM: Registered nosave memory: [mem
0x000f0000-0x000fffff]
Nov  8 16:23:59 xx-xx kernel: PM: Registered nosave memory: [mem
0xbffe0000-0xbfffffff]
Nov  8 16:23:59 xx-xx kernel: PM: Registered nosave memory: [mem
0xc0000000-0xfeffbfff]
Nov  8 16:23:59 xx-xx kernel: PM: Registered nosave memory: [mem
0xfeffc000-0xfeffffff]
Nov  8 16:23:59 xx-xx kernel: PM: Registered nosave memory: [mem
0xff000000-0xfffbffff]
Nov  8 16:23:59 xx-xx kernel: PM: Registered nosave memory: [mem
0xfffc0000-0xffffffff]
Nov  8 16:23:59 xx-xx kernel: please try 'cgroup_disable=memory' option if
you don't want memory cgroups
Nov  8 16:23:59 xx-xx kernel: Initializing cgroup subsys memory
Nov  8 16:23:59 xx-xx kernel: Freeing initrd memory: 17248k freed
Nov  8 16:23:59 xx-xx kernel: Non-volatile memory driver v1.3
Nov  8 16:23:59 xx-xx kernel: crash memory driver: version 1.1
Nov  8 16:23:59 xx-xx kernel: Freeing unused kernel memory: 1764k freed
Nov  8 16:24:00 xx-xx kernel: [TTM] Zone  kernel: Available graphics memory:
4005228 kiB
Nov  8 16:24:00 xx-xx kernel: [TTM] Zone   dma32: Available graphics memory:
2097152 kiB
Nov  8 17:36:48 xx-xx kernel: Reserving 161MB of memory at 688MB for
crashkernel (System RAM: 8191MB)
Nov  8 17:36:48 xx-xx kernel: Early memory node ranges
Nov  8 17:36:48 xx-xx kernel: PM: Registered nosave memory: [mem
0x0009f000-0x0009ffff]
Nov  8 17:36:48 xx-xx kernel: PM: Registered nosave memory: [mem
0x000a0000-0x000effff]
Nov  8 17:36:48 xx-xx kernel: PM: Registered nosave memory: [mem
0x000f0000-0x000fffff]
Nov  8 17:36:48 xx-xx kernel: PM: Registered nosave memory: [mem
0xbffe0000-0xbfffffff]
Nov  8 17:36:48 xx-xx kernel: PM: Registered nosave memory: [mem
0xc0000000-0xfeffbfff]
Nov  8 17:36:48 xx-xx kernel: PM: Registered nosave memory: [mem
0xfeffc000-0xfeffffff]
Nov  8 17:36:48 xx-xx kernel: PM: Registered nosave memory: [mem
0xff000000-0xfffbffff]
Nov  8 17:36:48 xx-xx kernel: PM: Registered nosave memory: [mem
0xfffc0000-0xffffffff]
Nov  8 17:36:48 xx-xx kernel: please try 'cgroup_disable=memory' option if
you don't want memory cgroups
Nov  8 17:36:48 xx-xx kernel: Initializing cgroup subsys memory
Nov  8 17:36:48 xx-xx kernel: Freeing initrd memory: 17824k freed
Nov  8 17:36:48 xx-xx kernel: Non-volatile memory driver v1.3
Nov  8 17:36:48 xx-xx kernel: crash memory driver: version 1.1
Nov  8 17:36:48 xx-xx kernel: Freeing unused kernel memory: 1984k freed
Nov  8 17:36:48 xx-xx kernel: Freeing unused kernel memory: 424k freed
Nov  8 17:36:48 xx-xx kernel: Freeing unused kernel memory: 556k freed
Nov  8 17:36:49 xx-xx kernel: [TTM] Zone  kernel: Available graphics memory:
4004518 kiB
Nov  8 17:36:49 xx-xx kernel: [TTM] Zone   dma32: Available graphics memory:
2097152 kiB
Nov  8 17:38:12 xx-xx kernel: Reserving 161MB of memory at 688MB for
crashkernel (System RAM: 8191MB)
Nov  8 17:38:12 xx-xx kernel: Early memory node ranges
Nov  8 17:38:12 xx-xx kernel: PM: Registered nosave memory: [mem
0x0009f000-0x0009ffff]
Nov  8 17:38:12 xx-xx kernel: PM: Registered nosave memory: [mem
0x000a0000-0x000effff]
Nov  8 17:38:12 xx-xx kernel: PM: Registered nosave memory: [mem
0x000f0000-0x000fffff]
Nov  8 17:38:12 xx-xx kernel: PM: Registered nosave memory: [mem
0xbffe0000-0xbfffffff]
Nov  8 17:38:12 xx-xx kernel: PM: Registered nosave memory: [mem
0xc0000000-0xfeffbfff]
Nov  8 17:38:12 xx-xx kernel: PM: Registered nosave memory: [mem
0xfeffc000-0xfeffffff]
Nov  8 17:38:12 xx-xx kernel: PM: Registered nosave memory: [mem
0xff000000-0xfffbffff]
Nov  8 17:38:12 xx-xx kernel: PM: Registered nosave memory: [mem
0xfffc0000-0xffffffff]
Nov  8 17:38:12 xx-xx kernel: please try 'cgroup_disable=memory' option if
you don't want memory cgroups
Nov  8 17:38:12 xx-xx kernel: Initializing cgroup subsys memory
Nov  8 17:38:12 xx-xx kernel: Freeing initrd memory: 17824k freed
Nov  8 17:38:12 xx-xx kernel: Non-volatile memory driver v1.3
Nov  8 17:38:12 xx-xx kernel: crash memory driver: version 1.1
Nov  8 17:38:12 xx-xx kernel: Freeing unused kernel memory: 1984k freed
Nov  8 17:38:12 xx-xx kernel: Freeing unused kernel memory: 424k freed
Nov  8 17:38:12 xx-xx kernel: Freeing unused kernel memory: 556k freed
Nov  8 17:38:13 xx-xx kernel: [TTM] Zone  kernel: Available graphics memory:
4004514 kiB
Nov  8 17:38:13 xx-xx kernel: [TTM] Zone   dma32: Available graphics memory:
2097152 kiB
Nov  8 18:35:12 xx-xx kernel: Reserving 161MB of memory at 688MB for
crashkernel (System RAM: 8191MB)
Nov  8 18:35:12 xx-xx kernel: Early memory node ranges
Nov  8 18:35:12 xx-xx kernel: PM: Registered nosave memory: [mem
0x0009f000-0x0009ffff]
Nov  8 18:35:12 xx-xx kernel: PM: Registered nosave memory: [mem
0x000a0000-0x000effff]
Nov  8 18:35:12 xx-xx kernel: PM: Registered nosave memory: [mem
0x000f0000-0x000fffff]
Nov  8 18:35:12 xx-xx kernel: PM: Registered nosave memory: [mem
0xbffe0000-0xbfffffff]
Nov  8 18:35:12 xx-xx kernel: PM: Registered nosave memory: [mem
0xc0000000-0xfeffbfff]
Nov  8 18:35:12 xx-xx kernel: PM: Registered nosave memory: [mem
0xfeffc000-0xfeffffff]
Nov  8 18:35:12 xx-xx kernel: PM: Registered nosave memory: [mem
0xff000000-0xfffbffff]
Nov  8 18:35:12 xx-xx kernel: PM: Registered nosave memory: [mem
0xfffc0000-0xffffffff]
Nov  8 18:35:12 xx-xx kernel: please try 'cgroup_disable=memory' option if
you don't want memory cgroups
Nov  8 18:35:12 xx-xx kernel: Initializing cgroup subsys memory
Nov  8 18:35:12 xx-xx kernel: Freeing initrd memory: 17824k freed
Nov  8 18:35:12 xx-xx kernel: Non-volatile memory driver v1.3
Nov  8 18:35:12 xx-xx kernel: crash memory driver: version 1.1
Nov  8 18:35:12 xx-xx kernel: Freeing unused kernel memory: 1984k freed
Nov  8 18:35:12 xx-xx kernel: Freeing unused kernel memory: 424k freed
Nov  8 18:35:12 xx-xx kernel: Freeing unused kernel memory: 556k freed
Nov  8 18:35:13 xx-xx kernel: [TTM] Zone  kernel: Available graphics memory:
4004514 kiB
Nov  8 18:35:13 xx-xx kernel: [TTM] Zone   dma32: Available graphics memory:
2097152 kiB
Nov  8 18:47:14 xx-xx kernel: Reserving 161MB of memory at 688MB for
crashkernel (System RAM: 8191MB)
Nov  8 18:47:14 xx-xx kernel: Early memory node ranges
Nov  8 18:47:14 xx-xx kernel: PM: Registered nosave memory: [mem
0x0009f000-0x0009ffff]
Nov  8 18:47:14 xx-xx kernel: PM: Registered nosave memory: [mem
0x000a0000-0x000effff]
Nov  8 18:47:14 xx-xx kernel: PM: Registered nosave memory: [mem
0x000f0000-0x000fffff]
Nov  8 18:47:14 xx-xx kernel: PM: Registered nosave memory: [mem
0xbffe0000-0xbfffffff]
Nov  8 18:47:14 xx-xx kernel: PM: Registered nosave memory: [mem
0xc0000000-0xfeffbfff]
Nov  8 18:47:14 xx-xx kernel: PM: Registered nosave memory: [mem
0xfeffc000-0xfeffffff]
Nov  8 18:47:14 xx-xx kernel: PM: Registered nosave memory: [mem
0xff000000-0xfffbffff]
Nov  8 18:47:14 xx-xx kernel: PM: Registered nosave memory: [mem
0xfffc0000-0xffffffff]
Nov  8 18:47:14 xx-xx kernel: please try 'cgroup_disable=memory' option if
you don't want memory cgroups
Nov  8 18:47:14 xx-xx kernel: Initializing cgroup subsys memory
Nov  8 18:47:14 xx-xx kernel: Freeing initrd memory: 17824k freed
Nov  8 18:47:14 xx-xx kernel: Non-volatile memory driver v1.3
Nov  8 18:47:14 xx-xx kernel: crash memory driver: version 1.1
Nov  8 18:47:14 xx-xx kernel: Freeing unused kernel memory: 1984k freed
Nov  8 18:47:14 xx-xx kernel: Freeing unused kernel memory: 424k freed
Nov  8 18:47:14 xx-xx kernel: Freeing unused kernel memory: 556k freed
Nov  8 18:47:15 xx-xx kernel: [TTM] Zone  kernel: Available graphics memory:
4004518 kiB
Nov  8 18:47:15 xx-xx kernel: [TTM] Zone   dma32: Available graphics memory:
2097152 kiB

os error message:
Nov  8 14:30:56 xx-xx kernel: postgres[26427]: segfault at 0 ip
00007f0e0a9e8641 sp 00007fff971a9598 error 4 in
libc-2.17.so[7f0e0a879000+1c3000]
Nov  8 14:31:41 xx-xx kernel: postgres[26453]: segfault at 0 ip
00007f0e0a9e8641 sp 00007fff971a9598 error 4 in
libc-2.17.so[7f0e0a879000+1c3000]
Nov  8 14:32:27 xx-xx kernel: postgres[26479]: segfault at 0 ip
00007f0e0a9e8641 sp 00007fff971a9598 error 4 in
libc-2.17.so[7f0e0a879000+1c3000]
Nov  8 14:33:12 xx-xx kernel: postgres[26523]: segfault at 0 ip
00007f0e0a9e8641 sp 00007fff971a9598 error 4 in
libc-2.17.so[7f0e0a879000+1c3000]
Nov  8 14:33:58 xx-xx kernel: postgres[26556]: segfault at 0 ip
00007f0e0a9e8641 sp 00007fff971a9598 error 4 in
libc-2.17.so[7f0e0a879000+1c3000]
Nov  8 14:40:43 xx-xx kernel: postgres[26571]: segfault at 0 ip
00007f0e0a9e8641 sp 00007fff971a9598 error 4 in
libc-2.17.so[7f0e0a879000+1c3000]

then i run the pg_dump
$ pg_dump -Fc -d testdb -f test-20191108.dump
pg_dump: error: schema with OID 7956828 does not exist

# select * from pg_namespace where oid = 7956828 ;
 oid | nspname | nspowner | nspacl
-----+---------+----------+--------
(0 rows)

please help me!!!







--
Sent from: https://www.postgresql-archive.org/PostgreSQL-bugs-f2117394.html


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Re: pg_dump: error: schema with OID 7956828 does not exist

Tomas Vondra-4
On Thu, Nov 07, 2019 at 11:59:24PM -0700, nemo wrote:

>Hello, I have a problem on PG12
>os:CentOS Linux release 7.4.1708 (Core)
>db:PostgreSQL 12.0
>
>the db log is
>2019-11-08 11:59:40.385 CST,,,19005,,5dc4e7d2.4a3d,1,,2019-11-08 11:58:10
>CST,1/0,0,WARNING,57P02,"terminating connection because of crash of another
>server process","The postmaster has commanded this server process to roll
>back the current transaction and exit, because another server process exited
>abnormally and possibly corrupted shared memory.","In a moment you should be
>able to reconnect to the database and repeat your command.",,,,,,"quickdie,
>postgres.c:2717","
>
>os message ,i find is not oom
>Nov  6 10:00:02 xx-xx crond: /usr/sbin/sendmail: Cannot allocate memory
>Nov  8 16:23:59 xx-xx kernel: Reserving 161MB of memory at 688MB for
>crashkernel (System RAM: 8191MB)
>Nov  8 16:23:59 xx-xx kernel: Early memory node ranges
>Nov  8 16:23:59 xx-xx kernel: PM: Registered nosave memory: [mem
>0x0009f000-0x0009ffff]
>Nov  8 16:23:59 xx-xx kernel: PM: Registered nosave memory: [mem
>0x000a0000-0x000effff]
>Nov  8 16:23:59 xx-xx kernel: PM: Registered nosave memory: [mem
>0x000f0000-0x000fffff]
>Nov  8 16:23:59 xx-xx kernel: PM: Registered nosave memory: [mem
>0xbffe0000-0xbfffffff]
>Nov  8 16:23:59 xx-xx kernel: PM: Registered nosave memory: [mem
>0xc0000000-0xfeffbfff]
>Nov  8 16:23:59 xx-xx kernel: PM: Registered nosave memory: [mem
>0xfeffc000-0xfeffffff]
>Nov  8 16:23:59 xx-xx kernel: PM: Registered nosave memory: [mem
>0xff000000-0xfffbffff]
>Nov  8 16:23:59 xx-xx kernel: PM: Registered nosave memory: [mem
>0xfffc0000-0xffffffff]
>Nov  8 16:23:59 xx-xx kernel: please try 'cgroup_disable=memory' option if
>you don't want memory cgroups
>Nov  8 16:23:59 xx-xx kernel: Initializing cgroup subsys memory
>Nov  8 16:23:59 xx-xx kernel: Freeing initrd memory: 17248k freed
>Nov  8 16:23:59 xx-xx kernel: Non-volatile memory driver v1.3
>Nov  8 16:23:59 xx-xx kernel: crash memory driver: version 1.1
>Nov  8 16:23:59 xx-xx kernel: Freeing unused kernel memory: 1764k freed
>Nov  8 16:24:00 xx-xx kernel: [TTM] Zone  kernel: Available graphics memory:
>4005228 kiB
>Nov  8 16:24:00 xx-xx kernel: [TTM] Zone   dma32: Available graphics memory:
>2097152 kiB
>Nov  8 17:36:48 xx-xx kernel: Reserving 161MB of memory at 688MB for
>crashkernel (System RAM: 8191MB)
>Nov  8 17:36:48 xx-xx kernel: Early memory node ranges
>Nov  8 17:36:48 xx-xx kernel: PM: Registered nosave memory: [mem
>0x0009f000-0x0009ffff]
>Nov  8 17:36:48 xx-xx kernel: PM: Registered nosave memory: [mem
>0x000a0000-0x000effff]
>Nov  8 17:36:48 xx-xx kernel: PM: Registered nosave memory: [mem
>0x000f0000-0x000fffff]
>Nov  8 17:36:48 xx-xx kernel: PM: Registered nosave memory: [mem
>0xbffe0000-0xbfffffff]
>Nov  8 17:36:48 xx-xx kernel: PM: Registered nosave memory: [mem
>0xc0000000-0xfeffbfff]
>Nov  8 17:36:48 xx-xx kernel: PM: Registered nosave memory: [mem
>0xfeffc000-0xfeffffff]
>Nov  8 17:36:48 xx-xx kernel: PM: Registered nosave memory: [mem
>0xff000000-0xfffbffff]
>Nov  8 17:36:48 xx-xx kernel: PM: Registered nosave memory: [mem
>0xfffc0000-0xffffffff]
>Nov  8 17:36:48 xx-xx kernel: please try 'cgroup_disable=memory' option if
>you don't want memory cgroups
>Nov  8 17:36:48 xx-xx kernel: Initializing cgroup subsys memory
>Nov  8 17:36:48 xx-xx kernel: Freeing initrd memory: 17824k freed
>Nov  8 17:36:48 xx-xx kernel: Non-volatile memory driver v1.3
>Nov  8 17:36:48 xx-xx kernel: crash memory driver: version 1.1
>Nov  8 17:36:48 xx-xx kernel: Freeing unused kernel memory: 1984k freed
>Nov  8 17:36:48 xx-xx kernel: Freeing unused kernel memory: 424k freed
>Nov  8 17:36:48 xx-xx kernel: Freeing unused kernel memory: 556k freed
>Nov  8 17:36:49 xx-xx kernel: [TTM] Zone  kernel: Available graphics memory:
>4004518 kiB
>Nov  8 17:36:49 xx-xx kernel: [TTM] Zone   dma32: Available graphics memory:
>2097152 kiB
>Nov  8 17:38:12 xx-xx kernel: Reserving 161MB of memory at 688MB for
>crashkernel (System RAM: 8191MB)
>Nov  8 17:38:12 xx-xx kernel: Early memory node ranges
>Nov  8 17:38:12 xx-xx kernel: PM: Registered nosave memory: [mem
>0x0009f000-0x0009ffff]
>Nov  8 17:38:12 xx-xx kernel: PM: Registered nosave memory: [mem
>0x000a0000-0x000effff]
>Nov  8 17:38:12 xx-xx kernel: PM: Registered nosave memory: [mem
>0x000f0000-0x000fffff]
>Nov  8 17:38:12 xx-xx kernel: PM: Registered nosave memory: [mem
>0xbffe0000-0xbfffffff]
>Nov  8 17:38:12 xx-xx kernel: PM: Registered nosave memory: [mem
>0xc0000000-0xfeffbfff]
>Nov  8 17:38:12 xx-xx kernel: PM: Registered nosave memory: [mem
>0xfeffc000-0xfeffffff]
>Nov  8 17:38:12 xx-xx kernel: PM: Registered nosave memory: [mem
>0xff000000-0xfffbffff]
>Nov  8 17:38:12 xx-xx kernel: PM: Registered nosave memory: [mem
>0xfffc0000-0xffffffff]
>Nov  8 17:38:12 xx-xx kernel: please try 'cgroup_disable=memory' option if
>you don't want memory cgroups
>Nov  8 17:38:12 xx-xx kernel: Initializing cgroup subsys memory
>Nov  8 17:38:12 xx-xx kernel: Freeing initrd memory: 17824k freed
>Nov  8 17:38:12 xx-xx kernel: Non-volatile memory driver v1.3
>Nov  8 17:38:12 xx-xx kernel: crash memory driver: version 1.1
>Nov  8 17:38:12 xx-xx kernel: Freeing unused kernel memory: 1984k freed
>Nov  8 17:38:12 xx-xx kernel: Freeing unused kernel memory: 424k freed
>Nov  8 17:38:12 xx-xx kernel: Freeing unused kernel memory: 556k freed
>Nov  8 17:38:13 xx-xx kernel: [TTM] Zone  kernel: Available graphics memory:
>4004514 kiB
>Nov  8 17:38:13 xx-xx kernel: [TTM] Zone   dma32: Available graphics memory:
>2097152 kiB
>Nov  8 18:35:12 xx-xx kernel: Reserving 161MB of memory at 688MB for
>crashkernel (System RAM: 8191MB)
>Nov  8 18:35:12 xx-xx kernel: Early memory node ranges
>Nov  8 18:35:12 xx-xx kernel: PM: Registered nosave memory: [mem
>0x0009f000-0x0009ffff]
>Nov  8 18:35:12 xx-xx kernel: PM: Registered nosave memory: [mem
>0x000a0000-0x000effff]
>Nov  8 18:35:12 xx-xx kernel: PM: Registered nosave memory: [mem
>0x000f0000-0x000fffff]
>Nov  8 18:35:12 xx-xx kernel: PM: Registered nosave memory: [mem
>0xbffe0000-0xbfffffff]
>Nov  8 18:35:12 xx-xx kernel: PM: Registered nosave memory: [mem
>0xc0000000-0xfeffbfff]
>Nov  8 18:35:12 xx-xx kernel: PM: Registered nosave memory: [mem
>0xfeffc000-0xfeffffff]
>Nov  8 18:35:12 xx-xx kernel: PM: Registered nosave memory: [mem
>0xff000000-0xfffbffff]
>Nov  8 18:35:12 xx-xx kernel: PM: Registered nosave memory: [mem
>0xfffc0000-0xffffffff]
>Nov  8 18:35:12 xx-xx kernel: please try 'cgroup_disable=memory' option if
>you don't want memory cgroups
>Nov  8 18:35:12 xx-xx kernel: Initializing cgroup subsys memory
>Nov  8 18:35:12 xx-xx kernel: Freeing initrd memory: 17824k freed
>Nov  8 18:35:12 xx-xx kernel: Non-volatile memory driver v1.3
>Nov  8 18:35:12 xx-xx kernel: crash memory driver: version 1.1
>Nov  8 18:35:12 xx-xx kernel: Freeing unused kernel memory: 1984k freed
>Nov  8 18:35:12 xx-xx kernel: Freeing unused kernel memory: 424k freed
>Nov  8 18:35:12 xx-xx kernel: Freeing unused kernel memory: 556k freed
>Nov  8 18:35:13 xx-xx kernel: [TTM] Zone  kernel: Available graphics memory:
>4004514 kiB
>Nov  8 18:35:13 xx-xx kernel: [TTM] Zone   dma32: Available graphics memory:
>2097152 kiB
>Nov  8 18:47:14 xx-xx kernel: Reserving 161MB of memory at 688MB for
>crashkernel (System RAM: 8191MB)
>Nov  8 18:47:14 xx-xx kernel: Early memory node ranges
>Nov  8 18:47:14 xx-xx kernel: PM: Registered nosave memory: [mem
>0x0009f000-0x0009ffff]
>Nov  8 18:47:14 xx-xx kernel: PM: Registered nosave memory: [mem
>0x000a0000-0x000effff]
>Nov  8 18:47:14 xx-xx kernel: PM: Registered nosave memory: [mem
>0x000f0000-0x000fffff]
>Nov  8 18:47:14 xx-xx kernel: PM: Registered nosave memory: [mem
>0xbffe0000-0xbfffffff]
>Nov  8 18:47:14 xx-xx kernel: PM: Registered nosave memory: [mem
>0xc0000000-0xfeffbfff]
>Nov  8 18:47:14 xx-xx kernel: PM: Registered nosave memory: [mem
>0xfeffc000-0xfeffffff]
>Nov  8 18:47:14 xx-xx kernel: PM: Registered nosave memory: [mem
>0xff000000-0xfffbffff]
>Nov  8 18:47:14 xx-xx kernel: PM: Registered nosave memory: [mem
>0xfffc0000-0xffffffff]
>Nov  8 18:47:14 xx-xx kernel: please try 'cgroup_disable=memory' option if
>you don't want memory cgroups
>Nov  8 18:47:14 xx-xx kernel: Initializing cgroup subsys memory
>Nov  8 18:47:14 xx-xx kernel: Freeing initrd memory: 17824k freed
>Nov  8 18:47:14 xx-xx kernel: Non-volatile memory driver v1.3
>Nov  8 18:47:14 xx-xx kernel: crash memory driver: version 1.1
>Nov  8 18:47:14 xx-xx kernel: Freeing unused kernel memory: 1984k freed
>Nov  8 18:47:14 xx-xx kernel: Freeing unused kernel memory: 424k freed
>Nov  8 18:47:14 xx-xx kernel: Freeing unused kernel memory: 556k freed
>Nov  8 18:47:15 xx-xx kernel: [TTM] Zone  kernel: Available graphics memory:
>4004518 kiB
>Nov  8 18:47:15 xx-xx kernel: [TTM] Zone   dma32: Available graphics memory:
>2097152 kiB
>
>os error message:
>Nov  8 14:30:56 xx-xx kernel: postgres[26427]: segfault at 0 ip
>00007f0e0a9e8641 sp 00007fff971a9598 error 4 in
>libc-2.17.so[7f0e0a879000+1c3000]
>Nov  8 14:31:41 xx-xx kernel: postgres[26453]: segfault at 0 ip
>00007f0e0a9e8641 sp 00007fff971a9598 error 4 in
>libc-2.17.so[7f0e0a879000+1c3000]
>Nov  8 14:32:27 xx-xx kernel: postgres[26479]: segfault at 0 ip
>00007f0e0a9e8641 sp 00007fff971a9598 error 4 in
>libc-2.17.so[7f0e0a879000+1c3000]
>Nov  8 14:33:12 xx-xx kernel: postgres[26523]: segfault at 0 ip
>00007f0e0a9e8641 sp 00007fff971a9598 error 4 in
>libc-2.17.so[7f0e0a879000+1c3000]
>Nov  8 14:33:58 xx-xx kernel: postgres[26556]: segfault at 0 ip
>00007f0e0a9e8641 sp 00007fff971a9598 error 4 in
>libc-2.17.so[7f0e0a879000+1c3000]
>Nov  8 14:40:43 xx-xx kernel: postgres[26571]: segfault at 0 ip
>00007f0e0a9e8641 sp 00007fff971a9598 error 4 in
>libc-2.17.so[7f0e0a879000+1c3000]
>
>then i run the pg_dump
>$ pg_dump -Fc -d testdb -f test-20191108.dump
>pg_dump: error: schema with OID 7956828 does not exist
>
># select * from pg_namespace where oid = 7956828 ;
> oid | nspname | nspowner | nspacl
>-----+---------+----------+--------
>(0 rows)
>
>please help me!!!
>

Clearly the postgres process is crashing because of segfault. Please see
[1] (there's a section about core dumps) and give us backtrace and other
details.

Other than that, it'd be interesting to know where does the schema OID
come from, so maybe investigate a bit in the server log and catalogs and
try to figure out which object is referring to the OID.

[1] https://wiki.postgresql.org/wiki/Getting_a_stack_trace_of_a_running_PostgreSQL_backend_on_Linux/BSD

regards

--
Tomas Vondra                  http://www.2ndQuadrant.com
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