业务需求，对日志表历史数据进行清理。历史表均很大，使用delete 操作删除90天前的数据。
第一部分：快速删除数据
SQL> alter table CC.F_LOG parallel 4; SQL>alter session enable parallel dml; SQL> delete FROM CC.F_LOG S WHERE S.CREATE_DATE>(SYSDATE-90);
执行计划确定并行
-----------------------------------------------
| Id | Operation |
-----------------------------------------------
| 0 | DELETE STATEMENT |
| 1 | PX COORDINATOR |
| 2 | PX SEND QC (RANDOM) |
| 3 | INDEX MAINTENANCE |
| 4 | PX RECEIVE |
| 5 | PX SEND RANGE |
| 6 | DELETE |
| 7 | BUFFER SORT |
| 8 | PX RECEIVE |
| 9 | PX SEND HASH (BLOCK ADDRESS)|
|* 10 | INDEX RANGE SCAN |
-----------------------------------------------
SQL> select INST_ID,sid,serial#,USERNAME,STATUS,MACHINE,SQL_ID,EVENT,(sysdate-LOGON_TIME)*86400 as "s",LAST_CALL_ET from gv$session where status='ACTIVE' and username is not null;
INST_ID SID SERIAL# USERNAME STATUS MACHINE SQL_ID EVENT s LAST_CALL_ET
------- ------ ------- ------------------- --------------- -------------------- ------------------------------ ------- ------------
1 24 44857 SYS ACTIVE p01 6yn37jfu2y88k PX Deq Credit: send blkd 190 189
1 584 28067 SYS ACTIVE p01 2ymxxw3mapxd9 SQL*Net message from client 196 0
1 884 40483 SYS ACTIVE p01 6yn37jfu2y88k PX Deq: Table Q Normal 190 189
1 888 8663 SYS ACTIVE p01 6yn37jfu2y88k PX Deq: Execute Reply 3679 212
1 1157 9679 SYS ACTIVE p01 6yn37jfu2y88k PX Deq: Table Q Normal 190 189
1 1162 10801 SYS ACTIVE p01 6yn37jfu2y88k direct path write temp 190 189
1 1437 22187 SYS ACTIVE p01 6yn37jfu2y88k PX Deq Credit: send blkd 190 189
1 1728 17227 SYS ACTIVE p01 6yn37jfu2y88k PX Deq Credit: send blkd 190 189
1 1740 25759 SYS ACTIVE p01 6yn37jfu2y88k PX Deq: Table Q Normal 190 189
9 rows selected.
删除完毕还原并行1
SQL> alter table CC.F_LOG parallel 1;
第二部分:数据删除hang
删除数据后发现，数据库会话数量越来越多，且delete操作session event
log file switch (archiving needed) 等待啥？需要等待日志切换归档完成？ 为啥等待日志切换归档这么长时间？ 观察alert
SQL> select INST_ID,sid,serial#,USERNAME,STATUS,MACHINE,SQL_ID,EVENT,(sysdate-LOGON_TIME)*86400 as "s",LAST_CALL_ET from gv$session where status='ACTIVE' and username is not null; INST_ID SID SERIAL# USERNAME STATUS MACHINE SQL_ID EVENT ------- ------ ------- -------------- ---------- -------------------- -------------------- ------------------------------ 1 597 51393 CXPT ACTIVE future-app1 fmmd0cjd0ghpf buffer busy waits 1 598 45595 ac ACTIVE pfmptom01.yutong.com 6d7v2nay5vm9n log file switch (archiving needed) 1 1429 41689 ac ACTIVE pfmptom02.yutong.com 3dn60pvzrqz0g buffer busy waits 1 1431 1279 CXPT ACTIVE future-app1 azakfbj8ss7f8 buffer busy waits 1 1449 1569 ac ACTIVE pfmptom01.yutong.com 7nbhsah5kw0q2 log file switch (archiving needed) 1 1453 25515 SYSTEM ACTIVE ZZYT\YT-P610764 1xz9mk73crhu8 log file switch (archiving needed) 1 1458 38363 ac ACTIVE pfmptom02.yutong.com 3dn60pvzrqz0g buffer busy waits 1 1709 27961 ac ACTIVE pfmptom01.yutong.com d8ats3n1vrm7t enq: US - contention 1 1714 62631 ac ACTIVE pfmptom01.yutong.com 0jg5553p23hup enq: SQ - contention 1 1716 57967 CXPT ACTIVE future-app2 azakfbj8ss7f8 enq: US - contention 1 1730 47159 ac ACTIVE pfmptom02.yutong.com 3dn60pvzrqz0g buffer busy waits 1 1731 10129 ac ACTIVE pfmptom01.yutong.com btgxyzwsc5sd1 enq: US - contention 1 2009 42483 ac ACTIVE pfmpbak01 94cs4sv2zua0u log file switch (archiving needed) 1 2033 64813 ac ACTIVE pfmptom02.yutong.com 3dn60pvzrqz0g buffer busy waits 48 rows selected.
观察ALERT日志，可以发现归档日志无法创建报错
Examine archive trace files for archiving errors
Current log# 8 seq# 41282 mem# 0: /oracle/oradata/fmpdb/redo08.log
Tue Aug 13 19:41:12 2019
ARC1: Encountered disk I/O error 19502
ARC1: Closing local archive destination LOG_ARCHIVE_DEST_1: '/oracle/archivelog/fmpdb_1_41278_961338832.log' (error 19502) (fmpdb)
ARC1: I/O error 19502 archiving log 4 to '/oracle/archivelog/fmpdb_1_41278_961338832.log'
ARCH: Archival stopped, error occurred. Will continue retrying
ORACLE Instance fmpdb - Archival Error
ORA-16038: log 4 sequence# 41278 cannot be archived
ORA-19502: write error on file "", block number (block size=)
ORA-00312: online log 4 thread 1: '/oracle/oradata/fmpdb/redo04.log'
Tue Aug 13 19:41:13 2019
ARCH: Archival stopped, error occurred. Will continue retrying
ORACLE Instance fmpdb - Archival Error
ORA-16014: log 4 sequence# 41278 not archived, no available destinations
ORA-00312: online log 4 thread 1: '/oracle/oradata/fmpdb/redo04.log'
Tue Aug 13 19:44:28 2019
minact-scn: useg scan erroring out with error e:12751
Tue Aug 13 19:46:14 2019
ARC1: Encountered disk I/O error 19502
ARC1: Closing local archive destination LOG_ARCHIVE_DEST_1: '/oracle/archivelog/fmpdb_1_41278_961338832.log' (error 19502) (fmpdb)
ARC1: I/O error 19502 archiving log 4 to '/oracle/archivelog/fmpdb_1_41278_961338832.log'
ARCH: Archival stopped, error occurred. Will continue retrying
ORACLE Instance fmpdb - Archival Error
ORA-16038: log 4 sequence# 41278 cannot be archived
ORA-19502: write error on file "", block number (block size=)
ORA-00312: online log 4 thread 1: '/oracle/oradata/fmpdb/redo04.log'
Tue Aug 13 19:46:14 2019
ARCH: Archival stopped, error occurred. Will continue retrying
ORACLE Instance fmpdb - Archival Error
ORA-16014: log 4 sequence# 41278 not archived, no available destinations
ORA-00312: online log 4 thread 1: '/oracle/oradata/fmpdb/redo04.log'
Tue Aug 13 19:49:35 2019
minact-scn: useg scan erroring out with error e:12751
Tue Aug 13 19:51:15 2019
ARC1: Encountered disk I/O error 19502
ARC1: Closing local archive destination LOG_ARCHIVE_DEST_1: '/oracle/ARC1: I/O error 19502 archiving log 4 to '/oracle/archivelog/fmpdb_1_41278_961338832.log'
ARCH: Archival stopped, error occurred. Will continue retrying
ORACLE Instance fmpdb - Archival Error
ORA-16038: log 4 sequence# 41278 cannot be archived
ORA-19502: write error on file "", block number (block size=)
ORA-00312: online log 4 thread 1: '/oracle/oradata/fmpdb/redo04.log'
ARCH: Archival stopped, error occurred. Will continue retrying
ORACLE Instance fmpdb - Archival Error
ORA-16014: log 4 sequence# 41278 not archived, no available destinations
ORA-00312: online log 4 thread 1: '/oracle/oradata/fmpdb/redo04.log'
Tue Aug 13 19:56:16 2019
Archiver process freed from errors. No longer stopped
Tue Aug 13 19:56:18 2019
Archived Log entry 41273 added for thread 1 sequence 41278 ID 0x67cfc4e dest 1:
krse_arc_driver_core: Successful archiving of previously failed ORL
Tue Aug 13 19:56:18 2019
Thread 1 advanced to log sequence 41283 (LGWR switch)
Current log# 4 seq# 41283 mem# 0: /oracle/oradata/fmpdb/redo04.log
Tue Aug 13 19:56:18 2019
Some DDE async actions failed or were cancelled
Tue Aug 13 19:56:23 2019
Archived Log entry 41274 added for thread 1 sequence 41281 ID 0x67cfc4e dest 1:
Archived Log entry 41275 added for thread 1 sequence 41279 ID 0x67cfc4e dest 1:
Archived Log entry 41276 added for thread 1 sequence 41280 ID 0x67cfc4e dest 1:
Archived Log entry 41277 added for thread 1 sequence 41282 ID 0x67cfc4e dest 1:
Tue Aug 13 19:56:43 2019
Thread 1 advanced to log sequence 41284 (LGWR switch)
Current log# 5 seq# 41284 mem# 0: /oracle/oradata/fmpdb/redo05.log
Tue Aug 13 19:56:45 2019
Archived Log entry 41278 added for thread 1 sequence 41283 ID 0x67cfc4e dest 1:
Tue Aug 13 19:57:10 2019
Thread 1 cannot allocate new log, sequence 41285
操作手工删除归档日志后，快速执行脚本压缩备份归档日志删除已备份的归档日志释放空间。 delete操作恢复且执行完毕后，对数据库立即进行全备份。
[root@pfmpodb01 ~]# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/VolGroup00-LogVol00 297G 297G 0G 100% /
清理归档日志
[root@pfmpodb01 ~]# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/VolGroup00-LogVol00 297G 271G 12G 97% /
压缩备份归档日志后删除日志
backup format '/oracle/dbbak/archbak_%d_%s_%p_%T' archivelog all delete input;
[root@pfmpodb01 archivelog]# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/VolGroup00-LogVol00 297G 230G 52G 82% /