…to other sessions. How to troubleshoot gap locks? Is possible to detect those gap locks using SHOW ENGINE INNODB…page…to change its value. Both options cause phantom reads (non repeatable reads) so in order to prevent problems with the replication you should change…
Post: Multi Range Read (MRR) in MySQL 5.6 and MariaDB 5.5
March 21, 2012 By 10 Comments
…Innodb_data_reads 120552 123872 100551 103011 77213 Innodb_pages_read 120548 123868 100551 123592 100566 Innodb…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…
Post: Join Optimizations in MySQL 5.6 and MariaDB 5.5
April 4, 2012 By 2 Comments
… Now let’s see how effective are the join…Innodb_data_reads 329115 355323 143808 335526 16164 15506 Innodb_pages_read 329115 355323 143808 358308 144798 144881 Innodb…Innodb_buffer_pool_read_ahead when the buffers are sized appropriately, which shows that the IO access pattern has been changed to…
Post: Index Condition Pushdown in MySQL 5.6 and MariaDB 5.5 and its performance impact
March 12, 2012 By 12 Comments
I have been working with Peter in preparation for the talk comparing the optimizer enhancements in MySQL 5.6 and MariaDB 5.5. We are taking a look at and benchmarking optimizer enhancements one by one. So in the same way this blog post is aimed at a new optimizer enhancement Index Condition …
Post: How to estimate time it takes Innodb to Recover ?
May 9, 2007 By 7 Comments
…by size of log files as Innodb needs to flush database pages to the …pages will need changes to be applied to them, but this is usually minor part of the workload compared to anything else as page…to handle and crash Innodb few times to see how long it takes Innodb to recover. I’d recommend to…
Post: Innodb row size limitation
April 7, 2011 By 11 Comments
…size, which is slightly less than half a database page (the actual math is 16k-(page header + page trailer)/2. For the default page size…Innodb‘s internal limitations), though you still need to change the way your application uses this data. You can limit the changes to…
Post: MySQL Users Conference - Innodb
May 9, 2007 By 6 Comments
…to specify single page size for Innodb table, while data pages and pages for different indexes may well have very different compression ratio. As Innodb…change to watch out for. So these are all possibilities but are we expected to…
Post: Innodb Caching (part 2)
May 10, 2011 By 7 Comments
…Innodb page size, 4KB page size as 16K page size compressed to 4. The data in this case compresses perfectly (all pages could be compressed to…size is almost 30% larger with 4K pages. In this case Percona Server 5.5 was tested, which allows changing page size…
Post: Real-Life Use Case for "Barracuda" InnoDB File Format
April 23, 2008 By 11 Comments
… using new InnoDB file format but in this post I’d like to share some real-life example how compression in InnoDB plugin could… fields. We’ve been trying to optimize this server before by playing with various innodb parameters (including page size changes) but at the end of the day server was dying of I/O load because dataset size was…
Post: SHOW INNODB STATUS walk through
July 17, 2006 By 40 Comments
…size of read requests. For random IO these should be 16K – page size…Innodb – pages to be flushed via LRU pages – dirty pages which were not accessed long time, flush list – old pages which need to…
