…cannot change at runtime from MySQL console wit SET or SET GLOBAL command. log_slow_filter=name Log only the queries … log_slow_rate_limit=# Rate limit statement writes to slow log to only those from every (1/log_slow_rate_limit) session. With high traffic coming to your database, the slow logging…
Post: 5.0.77 / 5.0.82 -build16 Percona binaries
June 11, 2009 By 4 Comments
… patches were added: profiling_slow.patch This patch adds information from SHOW PROFILE to query information in slow.log output. profiling_server. This… –with-debug Bug #381430: mysql-test profiling fails on 5.0.77 Bug #375494: log_slow_rate_limit logs all queries on a connection after a >1s query Bug #378761: compilation fails on 5.0.77 Bug #381900: mysql-test…
Post: Figuring out what limits MySQL Replication
March 7, 2007 By Leave a Comment
…limiting MySQL Replication speed. My first idea was to check it based on slow query log, happily the server was running MySQL with slow query log…
Post: InnoDB Flushing: a lot of memory and slow disk
March 31, 2011 By 57 Comments
…_log_file_size), MySQL 5.5.10 with innodb_adaptive_flushing=ON (default)). The problem here is that the system has quite slow… (and that is an important factor with slow disks); and 3) MySQL does not support innodb_log_file_size > 4GB (it is supported… memory, we need to have a throttling mechanism that will limit the rate of changes in memory. Optimize the flushing of sequential…
Post: Estimating Undo Space needed for LVM Snapshot
June 9, 2008 By 5 Comments
… First do not place logs in LVM, I mean binary logs, slow query log, general query log etc, if they … of logs during the time of backup you will need 10GB of undo space. Second, limit batch… rating summary tables recreation etc are also possible trouble makers. Third,Use dedicated LVM volume for MySQL…
Post: SHOW INNODB STATUS walk through
July 17, 2006 By 40 Comments
… OS Waits are relatively slow, and if you get…MySQL thread id 8079, query id 728899 localhost root Sending data select sql_calc_found_rows * from b limit…purposes only. — LOG — Log sequence number 84 3000620880 Log flushed up… bound workload with hit rate of 995/1000. ————– ROW OPERATIONS …
Post: Heikki Tuuri Innodb answers - Part I
October 26, 2007 By 19 Comments
…, if the page data size drops below this limit, merging it to a neighbor is tried */ #define… which slows down throughput. If we could control the checkpointing rate we could use an 8G write ahead log … so. Sergei Golubchik serialized the MySQL binlog write and the InnoDB log flush with a mutex in 5.1…
Post: Heikki Tuuri answers to Innodb questions, Part II
November 4, 2007 By 13 Comments
… smaller) or can a bit slow it down. Plus there were…the first file in the log file group and the SSD …to the drives at the rate of 100MB/sec or more…._size Q36: There have been several MySQL bugs opened about multi-core scalability …to quantify what are the limits of different operations for different …
Post: Analyzing air traffic performance with InfoBright and MonetDB
October 2, 2009 By 50 Comments
… InfoBright (ICE) version: 5.1.14-log build number (revision)=IB_3….limited and I had to transform files to quote each field. After that load statement is: mysql -S /tmp/mysql… wide range of rows, the slowness here is similar to Q0. -…in InfoBright is impressive. Even smaller rate 1:10 means you can …
Post: Effect of adaptive_flushing
December 4, 2009 By 5 Comments
…mysql> SHOW INNODB STATUS\G …. Database pages 2318457 Old database pages 855816 Modified db pages 457902 Log…slow (Yasufumi’s benchmarks show this very well). After enabling adaptive flushing we see a consistent and higher-than-previous-average rate… this system near its limitations so I am not…
