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3

(Sorry for the delay; there are some important issues.) The following things won't explain your mutex questions, but may improve performance such that the questions go away. Observations: Version: 5.5.41-MariaDB-wsrep 3.7 GB of RAM Uptime = 61d 21:40:40 You are not running on Windows. Running 64-bit version You appear to be running entirely (or mostly) ...


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What you see is the correct behaviour for the default isolation setting (REPEATABLE READ) and even for lower (READ COMMITTED) setting. More details can be found in MariaDB and MySQL docs: SET TRANSACTION Transaction Isolation Levels Consistent Nonlocking Reads which basically sums up to: What one transaction is writing, other transactions should not ...


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I have used it to create backups where I sleep until I can get a process ID from the processlist that is holding a database lock. I mentioned this idea back on Apr 17, 2011 in my answer to the post How can I optimize a mysqldump of a large database? I wrote the answer to another post Jun 20, 2012 that has the actual code where I demonstrated the use of ...


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From the symptoms, it seems that you are using InnoDB engine for your tables. If so, it is normal not to have accurate number of rows shown by clients (Like HeidiSQL or PHPMyAdmin). It is also worth it to mention that SHOW TABLE STATUS LIKE 'table_name' does not provide accurate row count for InnoDB tables. InnoDB estimates the number of rows in the ...


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You seem to not be connecting to the master that you think you are. Per your binary logs on the master you seem to have: #160519 3:28:59 server id 5 But per SHOW SLAVE STATUS we see: Master_Server_Id: 3 And further you seem to be connecting on localhost, but you implied your master/slave are on different hosts: Master_Host: 127....


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In a Galera cluster, any node can play the part of a Master node. Such a node can execute DML (INSERTs, UPDATEs, and DELETEs). If DML statements are spread across multiple Master nodes and are targeting the same tables, you must expect log conflicts. Why ? Galera wsrep libraries were designed to commit DML changes if all nodes in a cluster are ready to do ...


1

This information may not be of interest to the DBA. If the application is handling conflicts correctly, there is no need to log them. It would be expected behaviour. You would only enable this level of logging if you were debugging a specific issue. Otherwise it would generate a lot of spam in the logs.


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To setup mysql database server, follow step by step of below given URL http://www.cyberciti.biz/faq/how-to-install-mysql-under-rhel/


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In my experience setting up MariaDB 10.1 cluster, this behavior happens due to an override cnf file. I had the same problem, that changing a setting in my.cnf and restarting mysql but the change was ignored. I found on ubuntu there is /etc/mysql/conf.d/mariadb-enterprise.cnf which overrides many settings. I comment out in the override file the value I want ...


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I'm not an expert on mysql/mariadb, but I suspect that it is running the sub-query one for every row in CLD_DB.lnmntr, or at least every row it needs to until it finds 500 that match the condition (which might just be 500 or might be far more depending on your data). Some SQL engines are bright enough to see that the inner query is invariant within the ...



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