… is because virtual machines tend to handle process scheduling and timing much differently than traditional hardware, and I’ve seen situations…. For example, if you see a large number of long-running queries in the output of SHOW PROCESSLIST that might be a… and PRM simply attempt to connect and run a simple query, but it’s always possible to build something more involved…
Post: Rotating MySQL slow logs safely
April 18, 2013 By 7 Comments
… logs with long_query_time set to 0. Here are a some lessons we learned when logging a high volume of queries to the…_query.log { nocompress create 660 mysql mysql size 1G dateext missingok notifempty sharedscripts postrotate /usr/local/bin/mysql -e ‘select @@global.long_query_time into @lqt_save; set global long_query_time=2000; select sleep(2); FLUSH LOGS; select sleep(2); set global long_query_time=@lqt_save…
Comment: Rotating MySQL slow logs safely
April 18, 2013 By 7 Comments
… is if you are using persistent-connections. The global variable long_query_time is checked when the connection is created, so if you… feature to solve this issue. You can set the “slow_query_log_use_global_control” in 5.5 or “use_global… in 1 and the server will use the global variable long_query_time instead the local one. PS 5.1 http://www.percona…
Comment: Rotating MySQL slow logs safely
April 19, 2013 By 7 Comments
… the postrotate stanza 2a. Slow logging is paused (set global long_query_time=2000;) 2b. There is a small wait for buffered logs… are reopened (FLUSH LOGS;) 2d. Slow logging resumed (set global long_query_time=@lqt_save;)
Post: Is your MySQL buffer pool warm? Make it sweat!
April 16, 2013 By 6 Comments
… discarded designs and benchmarks.) First, we set long_query_time to 0 in order to log every query. (See part two for handling massive… –mysql-username playback –mysql-password PaSSwOrd –mysql-schema schema_name –query-log-stdin –dispatcher-plugin thread-pool –thread-pool-threads-count… is necessary when running a large stream of queries. Benchmarks We benchmarked with slow query logs captured from our production systems. We…
Post: MySQL and Percona Server in LinkBench benchmark
May 8, 2013 By 18 Comments
…%– buf_page_init_for_read(dberr_t*, unsigned long, unsigned long, unsigned long, unsigned long, long, unsigned long) … 31.41% 15534570 mysqld mysqld [.] rw_lock_x….53% 1338484 mysqld mysqld [.] ut_delay(unsigned long) So basically most of the time 5.6.11 spent in LRU_scan. I…=5000 table_open_cache=5000 table-definition-cache=1000 query_cache_size=0 query_cache_type=0 performance_schema=0 #56only loose…
Post: MySQL 5.6 Compatible Percona Toolkit 2.2 Released
March 25, 2013 By 2 Comments
… shouldn’t have a problem finding queries to run and compare. pt-query-digest is simpler pt-query-digest 2.2 has fewer…, we re-focused it on its primary objective: analyzing MySQL query logs. So the ability to parse memcached, Postgres, Apache, and… forever by default, so specify –iterations or –run-time to limit how long they run. There are more changes in addition to…
Post: More on MySQL transaction descriptors optimization
April 26, 2013 By Leave a Comment
… to Dimitri’s environment. To put a long story short, the results are fairly consistent …amount of updates to the database, all SELECT queries, even those participating in read-only transactions, …=1 –rand-type=uniform –forced-shutdown=1 –max-time=120 –max-requests=0 –percentile=99 –mysql-user…
Comment: MySQL caching methods and tips
March 27, 2013 By 5 Comments
… lately it behave strangely. Sometimes it load fine and anther time it wasn’t load at all. Checking the log file… same times. Maybe my only solution is to code the PHP to use less query and limit it to only make query which is not taking too long to retrieve. But with…
Post: Benchmarking Percona Server TokuDB vs InnoDB
May 7, 2013 By 32 Comments
… on this SSD to run this experiment that long. So there we see the strong side of TokuDB… to 60-sec checkpoint interval, as TokuDB does time-based checkpoints. These drops are quite concerning, and …buffer_size = 4M thread_cache_size = 1000 query_cache_size = 0 query_cache_type = 0 ft_min_word_len = 4…
