… the IO is slow (when the FS cache is cold, IO to slow IO subsystem happens)…MySQL 5.5 and MySQL 5.6 and innodb_old_blocks_time immediately came to mind. The InnoDB plugin introduced innodb…, p2.duration, p1.cpu_user + p1.cpu_system p1_cpu, p2.cpu_user + p2.cpu_system p2_cpu, p1.context_voluntary…
Post: Impact of logging on MySQL’s performance
February 10, 2009 By 8 Comments
… query; MySQL was run with default settings except following: [mysqld] user=root max_connections=3000 innodb_log_file_size=128M innodb_flush_log… different InnoDB buffer was used. In CPU-bound case innodb_buffer_pool_size=2G In IO-bound case innodb_buffer_pool_size=512M innodb_flush… to log slow queries with execution time bigger than a second without worry about performance impact in case of CPU-bound workload…
Post: MySQL 5.0, 5.1 and Innodb Plugin CPU Efficiency
December 3, 2008 By 15 Comments
… did it couple of weeks ago so MySQL 5.0.67, MySQL 5.1.29 and Innodb Plugin 1.0.1 were used… you would not only run MySQL plugin but also use new “Barracuda” Innodb format you see just 1% slow down with 2 cores… usually shows synchronization is the issue. Barracuda format uses more CPU while delivering better performance so it is probably better with…
Post: Side load may massively impact your MySQL Performance
November 13, 2011 By 7 Comments
… should have relatively little CPU needs and be bound by…mysql –mysql-host=localhost –mysql-table-engine=innodb –mysql-db=test –oltp-table-name=md_cache_test_small –oltp-table-size=1100000 –mysql-user=msandbox –mysql…running concurrently. mysqldump itself also slows down about 2x. What is …
Post: Identifying the load with the help of pt-query-digest and Percona Server
December 29, 2011 By 3 Comments
… the vanilla MySQL server, you would see an entry like this in the slow query log: # …InnoDB_IO_r_bytes: 16121856 InnoDB_IO_r_wait: 0.001414 # InnoDB_rec_lock_wait: 0.000000 InnoDB_queue_wait: 0.000000 # InnoDB…path/to/slow-query.log Note that executing pt-query-digest can be pretty CPU and memory …
Post: Are you designing IO bound or CPU bound application ?
December 20, 2006 By 10 Comments
…every second MySQL Consulting work or even more frequently. IO Bound workload is quite different from CPU bound… with 1000 messages in mailbox may start slowing things down. Now you may get few … (data locality) also becomes very important – if Innodb tables are used having simply auto_increment …
Post: Percona Server with XtraDB Case Study, Behind the Scenes
October 21, 2010 By 13 Comments
… stack traces showed InnoDB mutex contention, sometimes oprofile showed the query cache hogging the CPU, and so on… could be done without fixing these problems inside MySQL and InnoDB at the source code level, or …running on an EC2 server. EC2 has relatively slow virtual CPUs, and given that and the …
Post: Heikki Tuuri Innodb answers - Part I
October 26, 2007 By 19 Comments
… features in MySQL 5.1 Q15: How frequently does Innodb fuzzy checkpointing is activated HT: InnoDB flushes…slows down throughput. If we could control the checkpointing rate we could use an 8G write ahead log and tell innodb… not in the official InnoDB, though. PZ: If your load is CPU bound and you’re…
Post: SHOW INNODB STATUS walk through
July 17, 2006 By 40 Comments
… will be free already. OS Waits are relatively slow, and if you get tens of thousands of … amount of spin waits and spin rounds significant CPU resources may be wasted. It should come to …id 1148250464, thread declared inside InnoDB 442 mysql tables in use 1, locked 0 MySQL thread id 8079, query id …
Post: How to load large files safely into InnoDB with LOAD DATA INFILE
July 3, 2008 By 29 Comments
… cannot purge them, so everything gets bloated and slow. Even simple SELECT queries might have to scan…ENGINE=InnoDB DEFAULT CHARSET=utf8 Here’s the result of loading the entire 4GB file in one chunk: time mysql -… things to note: the load was probably mostly CPU-bound. vmstat showed from 1% to 3% I…
