… software RAID 10. Now let’s come to the MySQL configuration. MySQL Configuration I used Percona Server 5.5.22-55 for the tests. Following… = 800 innodb_read_io_threads = 8 innodb_write_io_threads = 4 innodb_file_per_table = 1 ## Disabling query cache query_cache… EC2 instance and MySQL. Now as far as the benchmark itself is concerned, I made no code changes to iiBench, and used…
Comment: How to load large files safely into InnoDB with LOAD DATA INFILE
May 9, 2012 By 28 Comments
… in MySQL 5.5 (vanilla version). “The big LOAD DATA INFILE clogs the binary log and slows replication down. If the load takes 4 hours on the master, it will cause the slave to fall 4 hours behind.” Yes, I agree…’ INTO TABLE some_data_table; Using this strategy, replication continues to happen without a hitch and the LOAD DATA can happen…
Post: Testing Intel SSD 520
May 1, 2012 By 7 Comments
…some strange small periodic drops. To better understand response time ranges, we need to switch to synchronous IO and vary …. I am still interesting in asynchronous IO, as MySQL 5.5 uses async IO for writes. Maybe 8 threads …=’y';fs=’16′;fsb=’13′;bw=’100′;ff=’4‘;pc=’4889F0′;b=’s'; pid=’…
Post: Join Optimizations in MySQL 5.6 and MariaDB 5.5
April 4, 2012 By 2 Comments
… the disks are 4 5.4K disks in Software RAID5. Also note that the following changes were made on MySQL 5.6 config: optimizer… time is for MySQL 5.6 which takes 0.16s less as compared to MySQL 5.5 While with join_buffer_size set to 6M and read_rnd_buffer_size set to 6M, the query time for MySQL 5.6…
Post: Multi Range Read (MRR) in MySQL 5.6 and MariaDB 5.5
March 21, 2012 By 10 Comments
… of MySQL 5.6 and MariaDB 5.5. Note that query cache is disabled during these benchmark runs and that the disks are 4 5.4K… the same for MariaDB 5.5 when compared to MySQL 5.5, and this does not make sense to me. Probably its due to a bug in how… compared to MySQL 5.5 MRR clearly changes the access pattern to sequential, and hence InnoDB is able to do many read_aheads. Another thing to take…
Post: Index Condition Pushdown in MySQL 5.6 and MariaDB 5.5 and its performance impact
March 12, 2012 By 12 Comments
… preparation for the talk comparing the optimizer enhancements in MySQL 5.6 and MariaDB 5.5. We are taking a look at and benchmarking… Index Condition Pushdown (ICP). Its available in both MySQL 5.6 and MariaDB 5.5 Now let’s take a look briefly at what…
Post: Joining many tables in MySQL - optimizer_search_depth
April 20, 2012 By 6 Comments
… optimization, and full query execution time to less than 50ms. Low values, such as 3,4 provided a bit better performance but… in MySQL 5.5 which can produce very expensive plan selections ? Investigating this further I found the following explanation from Timour Katchaounov in MySQL… would be more important than backward compatibility. In MySQL 5.6 things are likely to get even better handling joins of many tables…
Post: Announcement of Percona XtraDB Cluster 5.5.20 GA release
April 3, 2012 By 10 Comments
…to ask us any questions. Related talks: Tutorial on PL MySQL Conference Galera Synchronous Multi-Master Replication for MySQL. My talk on PL MySQL… minutes Benchmarking Galera replication overhead Percona Server 5.5.15 + Galera 21.1-beta2 State of …’;fs=’16′;fsb=’13′;bw=’100′;ff=’4‘;pc=’4889F0′;b=’s';…
Post: InnoDB's gap locks
March 27, 2012 By 14 Comments
… lock mode IX RECORD LOCKS space id 19 page no 4 n bits 80 index `age` of table `test`.`t` trx…/refman/5.1/en/innodb-locks-set.html. Conclusion MySQL uses REPEATABLE READ as the default isolation level so it needs to lock the index records and the gaps to avoid…
Post: How FLUSH TABLES WITH READ LOCK works with Innodb Tables
March 23, 2012 By 20 Comments
…to complete this statement. Lets look at what the problem is. As of MySQL 5.5…
