Database Administrator

Use HAProxy as MongoDB sharded cluster mongos Load Balancing MongoDB shard cluster entry mongos does not have a failover mechanism. The official recommendation is to deploy mongos and the application server together. It is inconvenient to deploy

Use HugePages to optimize memory performance Copyright:During reprinting, please use hyperlinks to indicate the original source and author information of the article and this statementHttp://blog.csdn.net/wenshuangzhu/article/details/440955651.

Notes for new SQL Server database DBAs Any optimization or modification is based on the business situation. You are welcome to make a picture of what may be wrong or inaccurate. 1. we recommend that you set auto-growth when creating a database to

The heartbeat timeout detection of ASM -- Delayed asm pst heart beats Recently, we have received the dismount of the ASM disk and the error "Waited 15 secs for write IO to PST". This is the unique heartbeat timeout detection of ASM, the ASM instance

Impact of InnoDB Isolation Mode on MySQL Performance I have written two articles over the past few months: one is the dangerous debt related to the history of InnoDB transactions, and the other is the truth about the serious performance problems

Redis persistence-How RDB works and Problems Working principle of Redis persistent RDB mode: Redis persistent RDB mode. Redis uses the copy on write mechanism of the fork command. When a snapshot is generated, the current process is completely

Improves the performance of JDBC batch operations and jdbc PerformanceJDBC When you use the insert into... VALUES () statement to INSERT data in batches, you should use the JDBC PreparedStatement batch operation method instead of using one

At intervals, hbase reads will pause for 10 s and solve the problem. hbase10s Cause: some time ago, because the heapsize of the region server was set to 16 GB, the block cache size was changed to 16 GB * 0.4 = 3.2 GB, check the log and the

Redis client 2.0.0 pipeline list rpop bug, redisrpop Description: The rpop of the list OF redis client 2.0.0 pipeline has a serious bug. When the rpop list is used, if the list is already empty, the Response from rpop is still not null, causing the

Solve the problem that eclipse does not recognize Android phones. eclipseandroid After setting up the Android development environment, it is no problem to use the simulator to run the Android program. However, after connecting the mobile phone to

Ogg configuration review (dml> ddl> sequnce), dmlsequnce dml configuration process and test overview Create a dedicated tablespace, schema, and authorization on the source. Create tablespace goldengate datafile 'golden000001. dbf 'size 100 m

Mongodb3.0 Performance Test Report 1: mongodb3.0 performance test Test environment: Servers: 6 X86 pcservers Cpu: single 8-core Memory: 64 GB Disk: raid 10 Operating System: centos 6.5 Mongodb: 3.0 Java DRIVER: 2.8.0 Jdk: 1.6 Network: Gigabit

Network-related or instance-specific errors occur when you establish a connection with SQL server. An error occurred while running the JOB after MSSQL 2005 database backup JOB is configured today: After some searches, it may be related to the

Mysql partition and instance demonstration, mysql partition instance demonstration I. Why partition? Requirement: big data. Solution: divide and conquer. Divides large tables and large indexes into a smaller operation unit. In mysql,

My MYSQL Study Notes (3) -- operators, mysql Study Notes 1. Security equals operator () Select null nullunion allselect null 1 union ALLSELECT 1 0 UNION allSELECT NULL = NULL Note that the difference between this operator and equal to (=) is

Oracle generates an AWR report and oracle generates an awr report.  Original Works are from the blog of "Deep Blue blog". You are welcome to reprint them. Please note the following source when reprinting them. Otherwise, you will be held legally

Latch: shared pool latch: library cache diagnostic script (latchprofx. SQL, latchprof. SQL), sonysharedlibraryThe execution method is as follows: @ D: \ latchprofx. SQL sid, name, laddr % cache 10000 @ D: \ latchprof. SQL sid, name, laddr % cache 100

Oracle RAC rebuilding OCR, Votedisk, and racvotedisk Haha, I just mentioned the last article. I was bored and started another test. Environment:OS: redhat 5.8DB: Oracle 10.2.0.5 raw device We need to develop the habit of backing up ocr and votedisk

Sharp SQL2014: Based on the window offset calculation, sql2014 window offset  SQL Server 2012 introduces four offset functions: LAG, LEAD, FIRST_VALUE, and LAST_VALUE, which are used to return an element from an offset of the current row, or from

MongDB basic learning (5) -- projection, paging, sorting, aggregation, and mongdb Paging MongDB basic learning (5) -- projection, paging, sorting, and aggregation Basic syntax Learning The Chinese New Year is coming soon, tomorrow is a lover, and