…memory available, and memory is what really really matters. High-Memory Quadruple Extra Large Instance 68.4 GB of memory…’s come to the MySQL configuration. MySQL Configuration I used Percona …performance. Other then that, I have also disabled query cache to avoid contention caused by query cache…
Post: Join Optimizations in MySQL 5.6 and MariaDB 5.5
April 4, 2012 By 2 Comments
…performed on table2. Of course this could mean a lot of random lookups in case the dataset does not fit into memory…cache_incremental=on’ optimizer_switch=’join_cache_hashed=on’ optimizer_switch=’join_cache_bka=on’ join_cache… status counters. Counter Name MySQL 5.5 MySQL 5.6 MySQL 5.6 w/ join_buffer_…
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: Multi Range Read (MRR) in MySQL 5.6 and MariaDB 5.5
March 21, 2012 By 10 Comments
… case of MySQL 5.5 and ~5 hours in case of MySQL 5.6 and MariaDB 5.5. Note that query cache is… were captured when performing the benchmark on IO bound workload, mentioned above. Counter Name MySQL 5.5 MySQL 5.6 MySQL 5.6 w… in the buffer. But there is no performance improvement when the workload is in-memory, in fact MRR adds extra sorting overhead…
Post: MySQL Server Memory Usage
May 17, 2006 By 18 Comments
… about memory usage are quite understandable. If you configure MySQL Server so it uses too small amount of memory it will likey perform suboptimally… them still can have very large memory consumption Innodb Table Cache. Innodb has its own table cache in which meta data about each…
Post: Why you should ignore MySQL's key cache hit ratio
February 28, 2010 By 27 Comments
… and forget it. If you have enough memory, who cares. The memory isn’t allocated until it’s used … in MySQL to guide your decisions. It is also not the be-all and end-all of MySQL performance, … expensive than hits, then you care about cache misses, not cache hits. A Key_read is not guaranteed …
Post: MySQL Performance on Memory Appliance
March 31, 2008 By 23 Comments
… out MySQL Performance on “Memory Appliance” by Violin Memory which can be used as extremely high speed storage system. I helped Violin Memory to optimize MySQL… and tested in such condition – normal case is to allocate cache memory to buffer pool so IOs will mostly come from drives…
Post: Read Buffers, mmap, malloc and MySQL Performance
September 12, 2007 By 8 Comments
… only global user data is expected to be cached on startup but even if it is …profile (often together with strace) are great tools for MySQL Performance analyses. Too many people end tuning on plans… with mmap is much slower than allocating from memory memory pool which process already “owns” and in …
Post: Cache Performance Comparison
August 9, 2006 By 73 Comments
… for MySQL Performance tuning ? Not surpising associative array cache performs the best, almost 4 times faster than APC shared memory cache – closest competitor. In real life performance difference can be evel larger as there will be some syncronization contention while accessing shared memory cache…
Post: MySQL Query Cache
July 27, 2006 By 69 Comments
… for MySQL Performance optimization tasks but there are number of things you need to know. First let me clarify what MySQL Query Cache is… multiple copies of the same data in cache effectively wasting memory. Distirbuted caching systems can effectively use memory on multiple systems so there is…
