因共享内存被清理导致资源池化环境运行失败的问题
一、问题现象
在openGauss资源池化集群使用过程中，出现主机业务中断，检查到主机gaussdb进程消失，备机升主。
[ctt_ltt@openGauss169 ~]$ ps ux
USER PID %CPU %MEM VSZ RSS TTY STAT START TIME COMMAND
ctt_ltt 9085 0.0 0.0 24768 14976 ? Ss Oct17 0:52 /usr/lib/systemd/systemd --user
ctt_ltt 9087 0.0 0.0 48640 26752 ? S Oct17 0:00 (sd-pam)
ctt_ltt 66813 1.6 0.0 16960 12352 ? S Oct17 23:50 /data/ctt_ltt/omm/openGauss/gauss/app/bin/om_monitor -L /data/ctt_ltt/omm/log/gaussdb/ctt_ltt/cm/om_monitor
ctt_ltt 67764 0.0 0.0 8256 3520 ? Ss Oct17 0:37 /usr/bin/ssh-agent -a /home/ctt_ltt/gaussdb_tmp/gauss_socket_tmp
ctt_ltt 307636 0.0 0.0 23552 11264 ? S 11:50 0:00 sshd: ctt_ltt@pts/2
ctt_ltt 307643 0.0 0.0 216512 6208 pts/2 Ss 11:50 0:00 -bash
ctt_ltt 307723 0.0 0.0 23168 11264 ? S 11:50 0:00 sshd: ctt_ltt@notty
ctt_ltt 307889 0.0 0.0 9984 5120 ? Ss 11:50 0:00 /usr/libexec/openssh/sftp-server -l INFO -f AUTH
ctt_ltt 308316 0.0 0.0 235456 11968 pts/2 S+ 11:50 0:00 gsql -d postgres -p 3500 -r
ctt_ltt 326980 0.0 0.0 217856 5504 pts/0 R+ 11:51 0:00 ps ux
ctt_ltt 605404 0.0 0.0 23552 11264 ? S 11:24 0:00 sshd: ctt_ltt@pts/0
ctt_ltt 605407 0.0 0.0 216704 6464 pts/0 Ss 11:24 0:00 -bash
ctt_ltt 605485 0.0 0.0 23168 11264 ? S 11:24 0:00 sshd: ctt_ltt@notty
ctt_ltt 605486 0.0 0.0 9984 5120 ? Ss 11:24 0:00 /usr/libexec/openssh/sftp-server -l INFO -f AUTH
ctt_ltt 606461 11.0 0.0 1999168 31232 ? Sl 11:24 2:58 /data/ctt_ltt/omm/openGauss/gauss/app/bin/cm_agent
ctt_ltt 606633 0.0 0.0 1412864 73024 ? Sl 11:24 0:00 gaussdb fenced UDF master process
ctt_ltt 606717 0.1 0.0 4795264 289792 ? Sl 11:24 0:01 /data/ctt_ltt/omm/openGauss/gauss/app/bin/cm_server
ctt_ltt 606935 14.6 0.0 2838400 121920 ? Sl 11:24 3:55 /data/ctt_ltt/omm/openGauss/gauss/app/bin/dssserver -D /data/ctt_ltt/omm/openGauss/dss_home
ctt_ltt 607308 1.2 0.0 5952 1728 ? Sl 11:25 0:20 perctrl 36 39
[ctt_ltt@openGauss169 ctt_ltt]$ cm_ctl query -Cvipd
[ CMServer State ]
node node_ip instance state
-------------------------------------------------------------------------------------
1 openGauss169 xx.xx.xx.xx 1 /data/ctt_ltt/omm/openGauss/cm/cm_server Standby
2 openGauss171 xx.xx.xx.xx 2 /data/ctt_ltt/omm/openGauss/cm/cm_server Primary
[ Defined Resource State ]
node node_ip res_name instance state
----------------------------------------------------------
1 openGauss169 xx.xx.xx.xx dms_res 6001 Deleted
2 openGauss171 xx.xx.xx.xx dms_res 6002 OnLine
1 openGauss169 xx.xx.xx.xx dss 20001 Deleted
2 openGauss171 xx.xx.xx.xx dss 20002 OnLine
[ Cluster State ]
cluster_state : Unavailable
redistributing : No
balanced : No
current_az : AZ_ALL
[ Datanode State ]
node node_ip instance state | node node_ip instance state
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
1 openGauss169 xx.xx.xx.xx 6001 3500 /data/ctt_ltt/omm/openGauss/dn1 P Down Manually stopped | 2 openGauss171 xx.xx.xx.xx 6002 3500 /data/ctt_ltt/omm/openGauss/dn1 S Standby Promoting
经过短暂业务中断后，备机升主完成，继续对外提供服务。
[ctt_ltt@openGauss169 ctt_ltt]$ cm_ctl query -Cvipd
[ CMServer State ]
node node_ip instance state
-------------------------------------------------------------------------------------
1 openGauss169 xx.xx.xx.xx 1 /data/ctt_ltt/omm/openGauss/cm/cm_server Standby
2 openGauss171 xx.xx.xx.xx 2 /data/ctt_ltt/omm/openGauss/cm/cm_server Primary
[ Defined Resource State ]
node node_ip res_name instance state
----------------------------------------------------------
1 openGauss169 xx.xx.xx.xx dms_res 6001 Deleted
2 openGauss171 xx.xx.xx.xx dms_res 6002 OnLine
1 openGauss169 xx.xx.xx.xx dss 20001 Deleted
2 openGauss171 xx.xx.xx.xx dss 20002 OnLine
[ Cluster State ]
cluster_state : Degraded
redistributing : No
balanced : No
current_az : AZ_ALL
[ Datanode State ]
node node_ip instance state | node node_ip instance state
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
1 openGauss169 xx.xx.xx.xx 6001 3500 /data/ctt_ltt/omm/openGauss/dn1 P Down Manually stopped | 2 openGauss171 xx.xx.xx.xx 6002 3500 /data/ctt_ltt/omm/openGauss/dn1 S Primary Normal
二、定位方法
检查故障节点pg_log日志，目录为$GAUSSLOG/pg_log/dn_xxxx，检查到如下错误打印：
2024-10-18 11:51:45.374 6711d94e.5535 [unknown] 281059349802912 dn_6001 0 dn_6001_6002 42809 0 [BACKEND] FATAL: semop(id=36012398) failed: Identifier removed
2024-10-18 11:51:45.374 6711d50c.1 [unknown] 281473410400272 [unknown] 0 dn_6001_6002 00000 0 [BACKEND] LOG: WAL file creator process (ThreadId 281059349802912) was terminated by signal 1: Hangup
2024-10-18 11:51:45.375 [postmaster][reaper][281473410400272] LOG: terminating any other active server processes
2024-10-18 11:51:45.375 [postmaster][reaper][281473410400272] LOG: WAL file creator process (ThreadId 281059349802912) exited with exit code 0
2024-10-18 11:51:45.375 [postmaster][reaper][281473410400272] LOG: the server process exits
三、问题根因
出现该错误的原因是信号量被移除，导致数据库内部线程运行出现错误，数据库自动退出。
四、解决方案
数据库运行环境上，应当避免清理共享内存，同时对于RemoveIPC参数也应当设置为false，详见关闭RemoveIPC。
意见反馈