Technology Life Series the Story of me and the data Center-- the first issue
The name "Xiao y" is a pseudonym that the author thought of temporarily. In fact, it doesn't have any special meaning. Let's just use it to represent a group of unknown IT people who dedicate their youth to various data centers.
What Xiao y wants to share with you today is the process of analyzing difficult and complicated diseases. If you have the patience to finish reading this case, there will be some gains more or less, and there will be no waste of Xiao y's painstaking efforts.
Specifically, it is an analysis process of intermittent partial suspension cases, and the report will remind the common risks and hidden dangers of the stable operation of Oracle database.
1 problem description
According to the customer, the application will be abnormal intermittently, and the operation, including a single insert record, cannot be completed for a long time. According to the customer, there may be a "deadlock" in the database, hoping to find the root cause of the problem and propose a solution to prevent the problem from happening again.
On December 23, 2015, the problem occurred again, and the customer contacted Xiao y again. Xiao y collected information and diagnosed faults remotely, and finally located the root cause of the problem.
Environment introduction:
Operating system >
INSERT INTO TABLE_NAME (COL1,COL2,COL3,COL4,COL5,COL6,COL7) VALUES (: 1) VALUES 2, 3, 4)
> >
SQL > oradebug setmypid
Statement processed.
SQL > oradebug hanganalyze 3
Hang Analysis in/ oracle/admin/xxdb/udump/xxdb_ora_14136.trc
SQL >
SQL > oradebug dump systemstate 266
Statement processed.
SQL > oradebug tracefile_name
/ oracle/admin/xxdb/udump/xxdb_ora_14136.trc
> >
PROCESS 19:
-
SO: c00000003949b948, type: 2, owner: 0000000000000000, flag: INIT/-/-/0x00
(process) Oracle pid=19, calls cur/top: c0000000397209b0/c0000000397209b0, flag: (0)-
Int error: 0, call error: 0, sess error: 0, txn error 0
(post info) last post received: 0 0121
Last post received-location: kcbzww
Last process to post me: c000000039496148 1 22
Last post sent: 0 0 121
Last post sent-location: kcbzww
Last process posted by me: c000000039496148 1 22
(latch info) wait_event=0 bits=0
Process Group: DEFAULT, pseudo proc: c000000039529928
O/S info: user: oracle, term: UNKNOWN, ospid: 11880
OSD pid info: Unix process pid: 11880, image: oracle@ap-machine-
* 2015-12-22 10 1414 53.431
Short stack dump:
Ksdxfstk () + 48
