wait event

CSS initialization in non-ASM of a single instance is waiting for event resolution Environment Description: Oracle 11.2.0.4 Single Instance Operating System: Microsoft (R) Windows (R) Server 2003 Enterprise x64 Edition The TOP wait events in the

Innodb row lock source code learning (1), innodb row lock source code Innodb is the most popular storage engine in mysql databases. Compared with other storage engines, innodb supports transactions and row-level locks. Today, I would like to share

Internal structure The B-Tree index is dumped into a tree-like form and rendered: alter session set events ‘immediate trace name treedump level INDEX_OBJECT_ID‘; sql> alter session SET events ' immediate trace name treedump level 126

1. Why check points must occur when the database switches logs? What is the significance of this checkpoint? A: The execution of dbwr is triggered. dbwr writes all dirty queues related to this log to the data file to shorten the time required for

In 10 Gb, enqueueTX waits for four types: 1.enq: TX In 10g, enqueue TX waits are divided into four categories: 1. enq: TX-row lock contention 2. enq: TX-index contention 3. enq: TX-ITL 4. enq: T In 10g, the enqueue TX wait is divided into four

In general, when performance problems are detected, we will collect AWR reports covering the time period in which the problem occurred-but it is best to collect AWR reports covering only one hour-if In general, when performance problems are detected,

According to the development feedback, the application will trigger an alarm at recently. The application log shows that the database connection pool is full and new connections are rejected. First, I made an ASH report (Report range: 7: 25 ~ ),

Let's take a big picture first:  SQL statement used: BYS @ ocm1> select dbms_rowid.rowid_relative_fno (rowid) file #, dbms_rowid.rowid_block_number (rowid) block #, deptno from bys. test; FILE # BLOCK # DEPTNO ------------------------------ 4 391 10

ObjectiveUnconsciously, the Technology Life series • I and the data center story came to the fourth issue. Small y again to meet with you!What do you do when you see a business system that is measuring the following wave-shaped TPS curve?650)

AWR in Oracle, all known as Automatic Workload Repository, is an automated load repository.AWR is one of the key tools for DBAs to understand the state of their operations, and the AWR report provides an overall understanding and targeted

Forum for help Last week, CD channel ZSL contact me, let me see him in the forum sent a help post "oracle11.2.1 entire library export can not use ", told me this is the actual work encountered problems, for this reason, the user's data has not been

The basic approach to Oracle performance optimization includes several steps, including: 1 set a reasonable target for Oracle performance optimization. 2 measure and record the current Oracle performance. 3 Determine the current Oracle

Oracle Automatic Performance statistics?? Efficient diagnosis of performance problems, need to provide complete statistics available, like the doctor to the patient's palpation, to be able to correctly diagnose, and then prescribe the corresponding

For performance problems or some of the more bizarre problems, there are many points you can start to analyze.Ready to write a series about using Ash/dba_hist_active_sess_history, with the Oradebug, with the Linux command strace,pstack or use and so

Generate the 10046 trace file:Sql> CREATE TABLE t10046 as SELECT * from Dba_objects; Table created. Sql> Select File_id,block_id,blocks from dba_extents where segment_name= ' T10046 '; file_id block_id BLOCKS------------------------------1

Enq:ms–contention Wait EventThe wait event occurs in the materialized view refresh operation, and during the refresh process, the process that is responsible for the refresh frequently locks the materialized view Log table sys.mlog$ to synchronize

The 10046 event is an extension of sql_trace, dubbed "the sql_trace of doping."Effective tracking Level:① Level 0: Sql_trace=fasle② Class 1: sql_trace=true, which is the default level③ Level 4: Level 1 + bound variable④ Level 8: Level 4 + Wait Event⑤

Tkprof It is Oracle it comes with a command plug-in tool whose primary function is to convert the original trace file to the type of the text file, for example, the simplest method, using the following:Tkprof LY_ORA_128636.TRC

Oracle Performance Analysis 1: Enabling SQL tracking and obtaining trace files when Oracle queries encounter efficiency problems, we often need to understand the problem so as to provide solutions to the problem. Oracle provides the trace

Use the wait interface in Oracle 10 Gb to diagnose performance problemsJohn is the database administrator of ACME bank, and the other end of the phone is the angry user bill. He complained that his database session was hung up. Most database