[20190228]Backup Restore Throttle sleep.txt

[20190228]Backup Restore Throttle sleep.txt --//别人的系统提供awr报表,看一下发现Backup Restore Throttle sleep等待事件.找到如下链接: --//http://blog.itpub.net/28211342/viewspace-2141191/=>rman备份产生等待事件. --//检查后面的参数resource_manager_plan非空,估计resource_manager_plan对磁盘有一定限制,导致出现该等待事件. --//从字面上里面,感觉限制rman备份的速率也可以重演该等待事件,测试看看. 1.环境: SYS@book> @ ver1 PORT_STRING                    VERSION        BANNER ------------------------------ -------------- -------------------------------------------------------------------------------- x86_64/Linux 2.4.xx            11.2.0.4.0     Oracle Database 11g Enterprise Edition Release 11.2.0.4.0 - 64bit Production --//修改rman配置如下: RMAN> CONFIGURE CHANNEL 1 DEVICE TYPE DISK RATE 128 K; new RMAN configuration parameters: CONFIGURE CHANNEL 1 DEVICE TYPE DISK RATE 128 K; new RMAN configuration parameters are successfully stored RMAN> CONFIGURE DEVICE TYPE DISK PARALLELISM 1 BACKUP TYPE TO BACKUPSET; old RMAN configuration parameters: CONFIGURE DEVICE TYPE DISK PARALLELISM 3 BACKUP TYPE TO BACKUPSET; new RMAN configuration parameters: CONFIGURE DEVICE TYPE DISK PARALLELISM 1 BACKUP TYPE TO BACKUPSET; new RMAN configuration parameters are successfully stored --//取消RMAN> CONFIGURE CHANNEL 1 DEVICE TYPE DISK clear ; 2.测试: RMAN> backup as copy datafile 1 format '/u01/backup/%b'; Starting backup at 2019-02-28 16:38:28 allocated channel: ORA_DISK_1 channel ORA_DISK_1: SID=94 device type=DISK channel ORA_DISK_1: starting datafile copy input datafile file number=00001 name=/mnt/ramdisk/book/system01.dbf --//慢 SYS@book> @ wait P1RAW            P2RAW            P3RAW P1  P2  P3  SID SERIAL# SEQ# EVENT                         STATUS   STATE   WAIT_TIME_MICRO SECONDS_IN_WAIT WAIT_CLASS ---------------- ---------------- ----- -- --- --- ---- ------- ---- ----------------------------- -------- ------- --------------- --------------- ---------- 000000000000005E 000000000000000B 00    94  11   0   94      11 3127 Backup Restore Throttle sleep ACTIVE   WAITING          913277               1 Other SYS@book> @ wait P1RAW            P2RAW            P3RAW P1  P2  P3  SID SERIAL# SEQ# EVENT                         STATUS   STATE   WAIT_TIME_MICRO SECONDS_IN_WAIT WAIT_CLASS ---------------- ---------------- ----- -- --- --- ---- ------- ---- ----------------------------- -------- ------- --------------- --------------- ---------- 000000000000005E 000000000000000B 00    94  11   0   94      11 3129 Backup Restore Throttle sleep ACTIVE   WAITING          400255               0 Other --//可以发现出现Backup Restore Throttle sleep等待事件,也就是讲限制磁盘IO也会导致该等待事件. user interrupt received Finished backup at 2019-02-28 16:42:30 RMAN-00571: =========================================================== RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS =============== RMAN-00571: =========================================================== RMAN-03099: job cancelled at user request --//太慢了,取消操作. 3.扩展知识: --//我有看一些链接,发现dbms_backup_restore包里面自带一个sleep函数. --//估计调用这个函数也能演示出这个等待事件. SYS@book> @ desc_proc sys DBMS_BACKUP_RESTORE SLEEP OWNER      PACKAGE_NAME         OBJECT_NAME SEQUENCE ARGUMENT_NAME        DATA_TYPE            IN_OUT    DEFAULTED ---------- -------------------- ----------- -------- -------------------- -------------------- --------- ---------- SYS        DBMS_BACKUP_RESTORE  SLEEP              1 SECS                 BINARY_INTEGER       IN        N --//执行如下: SYS@book> exec sys.DBMS_BACKUP_RESTORE.SLEEP( 100 ); ... --//打开新回话: SYS@book> @ wait P1RAW            P2RAW            P3RAW P1 P2  P3  SID SERIAL#  SEQ# EVENT                         STATUS   STATE   WAIT_TIME_MICRO SECONDS_IN_WAIT WAIT_CLASS ---------------- ---------------- ----- -- -- --- ---- ------- ----- ----------------------------- -------- ------- --------------- --------------- ---------- 0000000000000036 0000000000000047 00    54 71   0   54      71    40 Backup Restore Throttle sleep ACTIVE   WAITING         1343560               1 Other --//估计正确. 4.跟踪rman看看: RMAN> CONFIGURE CHANNEL 1 DEVICE TYPE DISK RATE 20M; old RMAN configuration parameters: CONFIGURE CHANNEL 1 DEVICE TYPE DISK RATE 10 M; new RMAN configuration parameters: CONFIGURE CHANNEL 1 DEVICE TYPE DISK RATE 20 M; new RMAN configuration parameters are successfully stored $ strace -fttx -o /tmp/a1 rman target / RMAN> backup as copy  datafile 1 format '/u01/backup/%b_o'; Starting backup at 2019-03-01 09:00:21 using target database control file instead of recovery catalog allocated channel: ORA_DISK_1 channel ORA_DISK_1: SID=54 device type=DISK channel ORA_DISK_1: starting datafile copy input datafile file number=00001 name=/mnt/ramdisk/book/system01.dbf output file name=/u01/backup/system01.dbf_o tag=TAG20190301T090022 RECID=21 STAMP=1001754060 channel ORA_DISK_1: datafile copy complete, elapsed time: 00:00:45 channel ORA_DISK_1: throttle time: 0:00:34 channel ORA_DISK_1: starting datafile copy copying current control file channel ORA_DISK_1: throttle time: 0:00:34  $ grep 'nanosleep(' /tmp/a1 | cut -f1 -d" " | sort | uniq -c       7 16036      34 16053 --//进程16053,调用 nanosleep({1, 0}, NULL) = 0,34次(也就是34秒),与rman的输出一致. --//跟踪如何调用有点蛮烦放弃!!