MySQL 5.7 parameter range_optimizer_max_mem_size

MySQL 5.7 (starting with 5.7.9) introduces new parameter “range_optimizer_max_mem_size”. It is possible you will never have need to change it – if you for example do not do some really heavy updates. But we do – updates over several thousands...

Linux hugepages and MySQL – Ubuntu / Debian

There are 2 different mechanisms of hugepages in Debian/Ubuntu: “standard” hugepages (must be specifically manually configured in apps) transparent hugepages (available to all apps without configuration but it is usually discouraged to use them for...

Experiences with high availability in MySQL cluster

Here are just some notes about MySQL high availability (HA) based on practical experiences. Companies have to grow to the point when they finally understand necessity for HA. It usually means their services for customers get so valuable (usually meaning SLAs fees are...

InnoDB buffer pool

caches data and indexes in memory caches also inserts and updates with enough memory InnoDB can act as “memory database” can be splited into more parts (if overall size of all of them is bigger then 1 GB) to improve performance parameters:...

Query cache

mySQL stores executed SELECT statements and its results in query cache if the same statement is executed again, results are taken from cache controled by parameter ” query_cache_size“