RMAN Restore異常終止，報錯：Cannot allocate memory

RMAN Restore異常終止，報錯：Cannot allocate memory

RMAN restore過程中報Cannot allocate memory

現象：
channel ORA_DISK_1: restoring datafile 00030 to +TESTDG/rac/datafile/users.292.817416403
channel ORA_DISK_1: reading from backup piece /UNID/full_eaope61n.bak
channel ORA_DISK_1: ORA-19870: error while restoring backup piece /UNID/full_eaope61n.bak
ORA-19501: read error on file "/UNID/full_eaope61n.bak", block number 6610944 (block size=8192)
ORA-27072: File I/O error
Linux-x86_64 Error: 12: Cannot allocate memory
Additional information: 4
Additional information: 6610944
Additional information: -1

failover to previous backup

RMAN-00571: ===========================================================
RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS ===============
RMAN-00571: ===========================================================
RMAN-03002: failure of restore command at 11/21/2013 17:21:50
RMAN-06026: some targets not found - aborting restore
RMAN-06023: no backup or copy of datafile 4 found to restore

連續幾次都報Linux-x86_64 Error: 12: Cannot allocate memory

RMAN Restore指令碼極其簡單：
restore command: nohup rman target / cmdfile=/home/Oracle/rman log=/home/oracle/rman.log &

[oracle@rac1 ~]$ cat /home/oracle/rman
restore database;
[oracle@rac1 ~]$

分析：
1、RMAN原庫與恢複目的庫配置相差較大：
source:
[oracle@JOADBTEST01 ~]$ free -g
 total used free shared buffers cached
Mem: 15 15 0 0 0 6
-/+ buffers/cache: 9 6
Swap: 17 1 15

target:
[root@rac1 ~]# free -g
 total used free shared buffers cached
Mem: 3 3 0 0 0 2
-/+ buffers/cache: 0 3
Swap: 5 1 4
2、客戶備份指令碼非常簡單：
cat backup.cmd
backup database;
沒有限制backup piece大小，200多G的庫最後只備份成了1個備份結果檔案：
所有的備資料檔案都備份到了一個大檔案中，該檔案大小為90多G。
診斷為：超大的備份結果檔案和目的主機超低的配置導致了記憶體出現瓶頸，導致了RMAN無法繼續工作，異常退出。

解決方案：
1.重新進行備份，限制backup piece大小為2G。
2.目的主機為虛擬機器，調高配置。

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