…memory available, and memory is what really really matters. High-Memory Quadruple Extra Large Instance 68.4 GB of memory…Now let’s come to the MySQL configuration. MySQL Configuration I used Percona Server 5…. mostly concerned with write performance, so I went ahead to choose a table structure with no…
Comment: Benchmarking single-row insert performance on Amazon EC2
May 16, 2012 By 11 Comments
… the performance difference is basically that factor of 4. The variance is lower with only the primary key because the entire table fits in main memory. Each row is on the order of 30 bytes in the primary table, and so….launchpad.net/~mdcallag/mysql-patch/mytools/annotate/head%3A/bench/ibench/iibench.py) is that it measures query performance too, so if…
Post: Joining many tables in MySQL - optimizer_search_depth
April 20, 2012 By 6 Comments
… than 1000 rows and doing it completely in memory. The plan optimizer picked was very good one, … yet making it unusable to check the optimizer performance. Solution for this problem was to use set …conflicting though as if we assume MySQL users do not join lots of tables (less than 7) when using …
Post: Join Optimizations in MySQL 5.6 and MariaDB 5.5
April 4, 2012 By 2 Comments
…, MySQL always uses Nested Loop Join to join two or more tables. What this means is that, select rows from first table participating… performed on table2. Of course this could mean a lot of random lookups in case the dataset does not fit into memory… for the best possible performance gain. This is not entirely visible in the manual either for MariaDB or MySQL, but you need…
Post: Multi Range Read (MRR) in MySQL 5.6 and MariaDB 5.5
March 21, 2012 By 10 Comments
…when performing the benchmark on IO bound workload, mentioned above. Counter Name MySQL 5.5 MySQL 5.6 MySQL 5…1 MRR range scans had to be performed. As in the table above you can with default buffer …buffer. But there is no performance improvement when the workload is in-memory, in fact MRR adds extra…
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: Dynamic row format for MEMORY tables
September 6, 2011 By 3 Comments
… 2008 Igor Chernyshev of eBay implemented true-VARCHAR support for MEMORY tables for MySQL 5.0. Although this patch did not add the… performance-critical application depending on MEMORY tables, they are no replacement for application-specific tests. We start by checking if there is any performance…
Post: Performance gotcha of MySQL memory tables
February 1, 2008 By 5 Comments
One performance gotcha with MEMORY tables you might know about comes from the fact it is the only MySQL storage engine which defaults to… comes from the fact MEMORY tables use HASH indexes by default. I’ve created rather similar test table: CREATE TABLE `test` ( `id` int(11… writes and do all the changes directly in memory. MyISAM however had to perform number of random writes to the key file…
Post: Drop table performance
April 20, 2011 By 22 Comments
… about DROP TABLE performance in InnoDB. (You can refer to Peter’s post http://www.mysqlperformanceblog.com/2011/02/03/performance-problem-with-innodb-and-drop-table/ and these bug reports: http://bugs.mysql.com/bug.php?id=51325 and http://bugs.mysql… pool: The more memory used, the slower DROP TABLE operates. MySQL 5.6.2 shows some improvement compared to MySQL 5.1.56, but…
Post: How much overhead is caused by on disk temporary tables
August 16, 2007 By 26 Comments
… temporary tables performance to avoid OS writes OS Write cache is not as efficient as I would hope, at least on Linux Performance… in memory MEMORY temporary tables can be 10-100 times faster than disk based MyISAM tables Hopefully MySQL will implement support of dynamic rows for MEMORY tables…
