Thank for looking into this Tom. Here's the output from PostgreSQL log: *** Postgresql Log: TopMemoryContext: 32768 total in 4 blocks; 7232 free (9 chunks); 25536 used Operator class cache: 8192 total in 1 blocks; 4936 free (0 chunks); 3256 used TopTransactionContext: 8192 total in 1 blocks; 6816 free (0 chunks); 1376 used MessageContext: 8192 total in 1 blocks; 7104 free (1 chunks); 1088 used smgr relation table: 8192 total in 1 blocks; 2872 free (0 chunks); 5320 used Portal hash: 8192 total in 1 blocks; 3912 free (0 chunks); 4280 used PortalMemory: 8192 total in 1 blocks; 8040 free (0 chunks); 152 used PortalHeapMemory: 1077575324 total in 115158 blocks; 1860896 free (115146 chunks); 1075714428 used ExecutorState: 8192 total in 1 blocks; 7928 free (0 chunks); 264 used ExprContext: 0 total in 0 blocks; 0 free (0 chunks); 0 used Relcache by OID: 8192 total in 1 blocks; 3896 free (0 chunks); 4296 used CacheMemoryContext: 516096 total in 6 blocks; 198480 free (2 chunks); 317616 used mort_ht: 1024 total in 1 blocks; 328 free (0 chunks); 696 used pg_depend_depender_index: 1024 total in 1 blocks; 256 free (0 chunks); 768 used pg_depend_reference_index: 1024 total in 1 blocks; 256 free (0 chunks); 768 used pg_index_indrelid_index: 1024 total in 1 blocks; 392 free (0 chunks); 632 used pg_type_typname_nsp_index: 1024 total in 1 blocks; 328 free (0 chunks); 696 used pg_type_oid_index: 1024 total in 1 blocks; 392 free (0 chunks); 632 used pg_trigger_tgrelid_tgname_index: 1024 total in 1 blocks; 328 free (0 chunks); 696 used pg_statistic_relid_att_index: 1024 total in 1 blocks; 328 free (0 chunks); 696 used pg_auth_members_member_role_index: 1024 total in 1 blocks; 328 free (0 chunks); 696 used pg_auth_members_role_member_index: 1024 total in 1 blocks; 328 free (0 chunks); 696 used pg_rewrite_rel_rulename_index: 1024 total in 1 blocks; 328 free (0 chunks); 696 used pg_proc_proname_args_nsp_index: 1024 total in 1 blocks; 256 free (0 chunks); 768 used pg_proc_oid_index: 1024 total in 1 blocks; 392 free (0 chunks); 632 used pg_operator_oprname_l_r_n_index: 1024 total in 1 blocks; 192 free (0 chunks); 832 used pg_operator_oid_index: 1024 total in 1 blocks; 392 free (0 chunks); 632 used pg_opclass_oid_index: 1024 total in 1 blocks; 392 free (0 chunks); 632 used pg_opclass_am_name_nsp_index: 1024 total in 1 blocks; 256 free (0 chunks); 768 used pg_namespace_oid_index: 1024 total in 1 blocks; 392 free (0 chunks); 632 used pg_namespace_nspname_index: 1024 total in 1 blocks; 392 free (0 chunks); 632 used pg_language_oid_index: 1024 total in 1 blocks; 392 free (0 chunks); 632 used pg_language_name_index: 1024 total in 1 blocks; 392 free (0 chunks); 632 used pg_inherits_relid_seqno_index: 1024 total in 1 blocks; 328 free (0 chunks); 696 used pg_index_indexrelid_index: 1024 total in 1 blocks; 392 free (0 chunks); 632 used pg_authid_oid_index: 1024 total in 1 blocks; 392 free (0 chunks); 632 used pg_authid_rolname_index: 1024 total in 1 blocks; 392 free (0 chunks); 632 used pg_database_datname_index: 1024 total in 1 blocks; 392 free (0 chunks); 632 used pg_conversion_oid_index: 1024 total in 1 blocks; 392 free (0 chunks); 632 used pg_conversion_name_nsp_index: 1024 total in 1 blocks; 328 free (0 chunks); 696 used pg_conversion_default_index: 1024 total in 1 blocks; 192 free (0 chunks); 832 used pg_class_relname_nsp_index: 1024 total in 1 blocks; 328 free (0 chunks); 696 used pg_class_oid_index: 1024 total in 1 blocks; 392 free (0 chunks); 632 used pg_cast_source_target_index: 1024 total in 1 blocks; 328 free (0 chunks); 696 used pg_attribute_relid_attnum_index: 1024 total in 1 blocks; 328 free (0 chunks); 696 used pg_attribute_relid_attnam_index: 1024 total in 1 blocks; 328 free (0 chunks); 696 used pg_amproc_opc_proc_index: 1024 total in 1 blocks; 256 free (0 chunks); 768 used pg_amop_opr_opc_index: 1024 total in 1 blocks; 328 free (0 chunks); 696 used pg_amop_opc_strat_index: 1024 total in 1 blocks; 256 free (0 chunks); 768 used pg_aggregate_fnoid_index: 1024 total in 1 blocks; 392 free (0 chunks); 632 used MdSmgr: 8192 total in 1 blocks; 7504 free (0 chunks); 688 used LockTable (locallock hash): 8192 total in 1 blocks; 3912 free (0 chunks); 4280 used Timezones: 47592 total in 2 blocks; 5968 free (0 chunks); 41624 used ErrorContext: 8192 total in 1 blocks; 8176 free (4 chunks); 16 used [2006-02-23 08:46:26 PST|[local]|mtrac|postgres] ERROR: out of memory [2006-02-23 08:46:26 PST|[local]|mtrac|postgres] DETAIL: Failed on request of size 134217728. ------------------------- *** Stack trace: I'm not having luck generating a stack trace so far. Following the gdb instructions, the create index statement never comes back with either the I/O error or a success (created index). I'm still trying to figure this out. Hopefully, the above from the server log may shed some light on the problem. Thanks again, ---- Husam Tomeh -----Original Message----- From: Tom Lane [mailto:tgl@xxxxxxxxxxxxx] Sent: Tuesday, February 14, 2006 3:49 PM To: Tomeh, Husam Cc: pgsql-performance@xxxxxxxxxxxxxx Subject: Re: [PERFORM] 0ut of Memory Error during Vacuum Analyze and Create Index "Tomeh, Husam" <htomeh@xxxxxxxxxxx> writes: > mtrac=# show maintenance_work_mem ; > maintenance_work_mem > ---------------------- > 1048576 <====== > (1 row) > mtrac=# > mtrac=# > mtrac=# create index mort_ht on mortgage(county_id,mtg_rec_dt); > ERROR: out of memory <=== > DETAIL: Failed on request of size 134217728. <=== It would be useful to look at the detailed allocation info that this (should have) put into the postmaster log. Also, if you could get a stack trace back from the error, that would be even more useful. To do that, * start psql * determine PID of connected backend (use pg_backend_pid()) * in another window, as postgres user, gdb /path/to/postgres backend-PID gdb> break errfinish gdb> cont * issue failing command in psql * when breakpoint is reached, gdb> bt ... stack trace printed here ... gdb> q regards, tom lane ********************************************************************** This message contains confidential information intended only for the use of the addressee(s) named above and may contain information that is legally privileged. If you are not the addressee, or the person responsible for delivering it to the addressee, you are hereby notified that reading, disseminating, distributing or copying this message is strictly prohibited. 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