… out Thinking Clearly About Performance by Cary Millsap. So how we can use this data to estimate capacity of MySQL system ? We… we’re running Innodb with MySQL we can use Innodb_data_reads , Innodb_data_writes, Innodb_os_log_fsyncs for your disk… ? You can take a look at procfs for MySQL process: root@ubuntu:/var/log/mysql# cat /proc/19018/stat 19018 (mysqld) S 1…
Post: Upgrading MySQL
January 5, 2010 By 24 Comments
… compatibility between version and so you can run MySQL 5.0 database with MySQL 5.1 with no problems in most cases… another meaning in MySQL 5.0 MySQL generally supports legacy storage format for a while, even if it is not clearly visible. mysqlcheck… final backup before upgrading and make sure to keep binary logs for some time, in case you run into some serious…
Post: Troubleshooting MySQL Memory Usage
March 21, 2012 By 5 Comments
… simple problem on the surface becomes challenge with MySQL because there are no clear resource usage metrics available, and so in most… >> ps.log ps aux | grep mysqld >> ps.log sleep 60 done Check for Table Cache Related Allocations There are cases when MySQL will… and fixed. This is where your MySQL Support contract can be handy. Conclusion Understanding where MySQL can allocate memory can help us…
Post: Multiple purge threads in Percona Server 5.1.56 and MySQL 5.6.2
May 3, 2011 By 13 Comments
…were innodb_buffer_pool_size=16G innodb_log_file_size=1900M innodb_flush_log_at_trx_commit=2 innodb_…not to penalize further TPS. MySQL 5.6.2 Results Now let’s test MySQL 5.6.2. It is… data presented the other way: Here it becomes very clear that there are no significant differences caused by varying…
Post: Which Linux distribution for a MySQL database server? A specific point of view.
December 8, 2011 By 38 Comments
… MYSQL, upgrade MySQL, 10x start/stop MySQL, upgrade MySQL, downgrade MySQL, upgrade MySQL, install a security fix for something, 20x start/stop MySQL, upgrade MySQL, … . Restarting and changing MySQL… for package management. There isn’t a month that I log in to a system based on either distribution where there…’s required of them – stop or start MySQL. No problems there. It’s now clear that I never recommend Debian or Ubuntu…
Post: How Percona diagnoses MySQL server stalls
March 3, 2011 By 6 Comments
… all you need. Finally, make sure that the script can log into MySQL (if necessary, put a password into .my.cnf, or…, but not always. Most of the time the problem is clear upon a closer inspection, though. If the answer is not…. There are many things that can cause a stall in MySQL, and they usually begin microscopically and get worse over time…
Post: The relationship between Innodb Log checkpointing and dirty Buffer pool pages
February 17, 2012 By 10 Comments
… Innodb Log Checkpointing So, first of all, what can we see about Innodb log checkpointing and what does it tell us? mysql> SHOW ENGINE INNODB STATUS\G — LOG — Log sequence number 9682004056 Log flushed up to… more effective there in choosing older dirty pages. It is clear how that algorithm works without reading the source code. There…
Post: Can MySQL temporary tables be made safe for statement-based replication?
May 26, 2008 By 8 Comments
…_Log_File: mysql-bin.000006 Read_Master_Log_Pos: 98 Relay_Log_File: mysql_sandbox20551-relay-bin.000028 Relay_Log_Pos: 235 Relay_Master_Log_File: mysql-bin… master_log_file=’mysql-bin.000007′, master_log_pos=207; slave1 > show slave status\G *************************** 1. row *************************** Master_Log_File: mysql-bin.000007 …. omitted …….. Exec_Master_Log… all the statements went into the binlog individually, there’s clearly an opportunity to break replication here. It looks like this…
Post: How Percona does a MySQL Performance Audit
November 24, 2008 By 17 Comments
…/my.cnf –pid-file=/var/run/mysqld/mysqld.pid –log-error=/var/log/mysqld.log mysql 3172 3137 78 Nov19 ? 1-11:17:30…, I explain the meaning of the output, so it’s clear what I’m showing them. Then, I go through it… the Percona patches for microsecond logging and additional information in the slow query log output. The stock MySQL server’s limitation of one…
Post: Recovery deleted ibdata1
August 10, 2012 By 9 Comments
… deleted the InnoDB main table space – ibdata1 – and redo logs – ib_logfile*. MySQL keeps InnoDB files open all the time. The following… checkpoint age is zero, all pages are flushed: — LOG — Log sequence number 363096003 Log flushed up to 363096003 Last checkpoint at 363096003 Max… files ibdata and ib_logfile* do exist Do not restart MySQL until the further recovery strategy is clear
