Hi Wenjing, Please check, the server getting crash with the below scenario(CLUSTER gtt using INDEX).
*-- Session1:* postgres=# create global temporary table gtt (c1 integer) on commit preserve rows; CREATE TABLE postgres=# create index idx1 on gtt (c1); CREATE INDEX *-- Session2:* postgres=# create index idx2 on gtt (c1); CREATE INDEX *-- Session1:* postgres=# cluster gtt using idx1; 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. !?> *-- Below is the stacktrace:* [edb@localhost bin]$ gdb -q -c data/core.95690 postgres Reading symbols from /home/edb/PG/PGsrcNew/postgresql/inst/bin/postgres...done. [New LWP 95690] [Thread debugging using libthread_db enabled] Using host libthread_db library "/lib64/libthread_db.so.1". Core was generated by `postgres: edb postgres [local] CLUSTER '. Program terminated with signal 6, Aborted. #0 0x00007f9c574ee337 in raise () from /lib64/libc.so.6 Missing separate debuginfos, use: debuginfo-install glibc-2.17-292.el7.x86_64 keyutils-libs-1.5.8-3.el7.x86_64 krb5-libs-1.15.1-37.el7_7.2.x86_64 libcom_err-1.42.9-16.el7.x86_64 libgcc-4.8.5-39.el7.x86_64 libselinux-2.5-14.1.el7.x86_64 openssl-libs-1.0.2k-19.el7.x86_64 pcre-8.32-17.el7.x86_64 zlib-1.2.7-18.el7.x86_64 (gdb) bt #0 0x00007f9c574ee337 in raise () from /lib64/libc.so.6 #1 0x00007f9c574efa28 in abort () from /lib64/libc.so.6 #2 0x0000000000ab3a3c in ExceptionalCondition (conditionName=0xb5e2e8 "!ReindexIsProcessingIndex(indexOid)", errorType=0xb5d365 "FailedAssertion", fileName=0xb5d4e9 "index.c", lineNumber=3825) at assert.c:67 #3 0x00000000005b0412 in reindex_relation (relid=16384, flags=2, options=0) at index.c:3825 #4 0x000000000065e36d in finish_heap_swap (OIDOldHeap=16384, OIDNewHeap=16389, is_system_catalog=false, swap_toast_by_content=false, check_constraints=false, is_internal=true, frozenXid=491, cutoffMulti=1, newrelpersistence=103 'g') at cluster.c:1448 #5 0x000000000065ccef in rebuild_relation (OldHeap=0x7f9c589adef0, indexOid=16387, verbose=false) at cluster.c:602 #6 0x000000000065c757 in cluster_rel (tableOid=16384, indexOid=16387, options=0) at cluster.c:418 #7 0x000000000065c2cf in cluster (stmt=0x2cd1600, isTopLevel=true) at cluster.c:180 #8 0x000000000093b213 in standard_ProcessUtility (pstmt=0x2cd16c8, queryString=0x2cd0b30 "cluster gtt using idx1;", context=PROCESS_UTILITY_TOPLEVEL, params=0x0, queryEnv=0x0, dest=0x2cd19a8, qc=0x7ffcd32604b0) at utility.c:819 #9 0x000000000093aa50 in ProcessUtility (pstmt=0x2cd16c8, queryString=0x2cd0b30 "cluster gtt using idx1;", context=PROCESS_UTILITY_TOPLEVEL, params=0x0, queryEnv=0x0, dest=0x2cd19a8, qc=0x7ffcd32604b0) at utility.c:522 #10 0x00000000009398c2 in PortalRunUtility (portal=0x2d36ba0, pstmt=0x2cd16c8, isTopLevel=true, setHoldSnapshot=false, dest=0x2cd19a8, qc=0x7ffcd32604b0) at pquery.c:1157 #11 0x0000000000939ad8 in PortalRunMulti (portal=0x2d36ba0, isTopLevel=true, setHoldSnapshot=false, dest=0x2cd19a8, altdest=0x2cd19a8, qc=0x7ffcd32604b0) at pquery.c:1303 #12 0x0000000000938ff6 in PortalRun (portal=0x2d36ba0, count=9223372036854775807, isTopLevel=true, run_once=true, dest=0x2cd19a8, altdest=0x2cd19a8, qc=0x7ffcd32604b0) at pquery.c:779 #13 0x00000000009331b0 in exec_simple_query (query_string=0x2cd0b30 "cluster gtt using idx1;") at postgres.c:1239 #14 0x00000000009371bc in PostgresMain (argc=1, argv=0x2cfab80, dbname=0x2cfaa78 "postgres", username=0x2cfaa58 "edb") at postgres.c:4315 #15 0x00000000008872a9 in BackendRun (port=0x2cf2b50) at postmaster.c:4510 #16 0x0000000000886a9e in BackendStartup (port=0x2cf2b50) at postmaster.c:4202 #17 0x000000000088301c in ServerLoop () at postmaster.c:1727 #18 0x00000000008828f3 in PostmasterMain (argc=3, argv=0x2ccb460) at postmaster.c:1400 #19 0x0000000000789c54 in main (argc=3, argv=0x2ccb460) at main.c:210 (gdb) -- With Regards, Prabhat Kumar Sahu EnterpriseDB: http://www.enterprisedb.com