… all interested in MySQL. We really want you to be there — and that’s why we’re giving away free tickets and…, and then post another blog entry here to announce the results. Make sure we (or our sponsor) can contact you privately… other expenses. Ten second prizes are a free copy of the new book “High Performance MySQL, 3rd Edition” which will be available…
Post: Troubleshooting MySQL Memory Usage
March 21, 2012 By 3 Comments
…size 7864319 Buffer pool size, bytes 128849002496 Free buffers 1 Database pages 8252672 Old … correspond to global memory allocation and will result in increased memory allocation until server is … is where your MySQL Support contract can be handy. Conclusion Understanding where MySQL can allocate …
Post: Index Condition Pushdown in MySQL 5.6 and MariaDB 5.5 and its performance impact
March 12, 2012 By 12 Comments
… in preparation for the talk comparing the optimizer enhancements in MySQL 5.6 and MariaDB 5.5. We are taking a… optimizer enhancement Index Condition Pushdown (ICP). Its available in both MySQL 5.6 and MariaDB 5.5 Now let’s take…
Post: Handling big result sets
June 26, 2006 By 13 Comments
… = ‘SELECT * FROM longf’; $result = mysql_query($query) or die(‘Query failed: ‘ . mysql_error()); // retrive result while ($line = mysql_fetch_array($result, MYSQL_NUM)) { } // Free resultset mysql_free_result($result); $time_end = microtime(true); $time = $time_end – $time_start; echo “execution time: “.$time.” s”; mysql…
Post: MySQL net_write_timeout vs wait_timeout and protocol notes
July 8, 2007 By 1 Comment
… partial query received. Result set however comes back in multiple pieces and if you’re using mysql_use_result you can do any… comes from simplicity of MySQL protocol which does not allow client to talk to the server until full result set is fetched. This is also the reason why you can’t stop fetching for ordinary statements and mysql_free_result will…
Post: Helgrinding MySQL with InnoDB for Synchronisation Errors, Fun and Profit
November 24, 2011 By 2 Comments
… not need much introduction, especially to the MySQL server developers. The Valgrind Memcheck tool, ….ic:221) ==9090== by 0x6B39223: fsp_fill_free_list (fsp0fsp.c:1455) ==9090== by 0x6B3DED8… by 0x6A87FC: handle_select(THD*, st_lex*, select_result*, unsigned long) (sql_select.cc:269) ==9090== …
Post: Ultimate MySQL variable and status reference list
January 8, 2011 By 4 Comments
… constantly referring to the amazing MySQL manual, especially the option and variable reference table. But …proxy_userblogpercona.commanual pseudo_thread_idblogpercona.commanual Qcache_free_blocksblogpercona.commanual Qcache_free_memoryblogpercona.commanual Qcache_hitsblogpercona.commanual Qcache_…
Post: How to debug long-running transactions in MySQL
March 8, 2011 By 6 Comments
…}” ]; then echo “Exiting, not enough free space (${full}%, ${avail}MB free)”>&2 exit 1 fi host=$(mysql -ss -e ‘SELECT p.HOST FROM… port 3306 and port ${port} > /root/tcpdumps/`date +%s`-tcpdump & mysql -e ‘show innodb status\Gshow full processlist’ > /root/tcpdumps/`date +%s… “mk-query-digest –type=tcpdump –no-report –print” on the resulting tcpdump file (after inspecting the captured SHOW INNODB STATUS and…
Post: How to Monitor MySQL with Percona's Nagios Plugins
February 22, 2012 By 8 Comments
…and in many cases also don’t log the resulting errors. The best place to fix these problems … a system reboot. The pmp-check-mysql-pidfile plugin verifies that MySQL‘s PID file exists. Evidence of… too much memory and/or for too little free memory in general. This plugin requires careful configuration…
Post: How to convert MySQL's SHOW PROFILES into a real profile
February 20, 2012 By 10 Comments
…database to demonstrate: mysql> SET profiling=1; mysql> pager cat > /dev/null mysql> SELECT * FROM… | 0.018478 | 10.70 | 3 | 0.0061593333 | | Sorting result | 0.011090 | 6.42 | 1 | 0.0110900000 | |…| starting | 0.000032 | 0.02 | 1 | 0.0000320000 | | freeing items | 0.000027 | 0.02 | 2 | 0.0000135000 |…
