Emergency

Search Results for: innodb_flush_logs_at_trx_commit

Recovery beyond data restore

Quite frequently I see customers looking at MySQL recovery as on ability to restore data from backup which can be far from being enough to restore the whole system to operating state, especially for complex …

Read More
 

MySQL File System Fragmentation Benchmarks

Few days ago I wrote about testing writing to many files and seeing how this affects sequential read performance. I was very interested to see how it shows itself with real tables so I’ve got …

Read More
 

Innodb usability and ease of use.

It always surprised me how little Innodb team seems to think about product usability/ease of use, when it comes to settings, performance management etc. I could understand many things 5 years ago, like a lot …

Read More
 

MySQL 4 to MySQL 5 Upgrade performance regressions

This week I already had two serious performance regression cases when upgrading from MySQL 4.0 and 4.1 to MySQL 5.0. By serious I mean several times performance difference not just 5-10% you often see for …

Read More
 

SHOW INNODB STATUS walk through

Many people asked me to publish a walk through SHOW INNODB STATUS output, showing what you can learn from SHOW INNODB STATUS output and how to use this info to improve MySQL Performance. To start …

Read More
 

InnoDB thread concurrency

InnoDB has a mechanism to regulate count of threads working inside InnoDB. innodb_thread_concurrency is variable which set this count, and there are two friendly variables innodb_thread_sleep_delay and innodb_concurrency_tickets. I’ll try to explain how it works. …

Read More
 

Jeremy Cole on MySQL Replication

Jeremy Cole recently posted very nice post about MySQL Replication Performance. There are however few points I should comment on. Jeremy Speaks about MyISAM and Innodb in the same terms, in fact they are quite …

Read More