… InnoDB memory usage diagnostics. Bugs Fixed: Fix for bug #1131187 introduced a regression that could cause a memory leak if query cache was… the CVE-2012-5627 vulnerability, where an unprivileged MySQL account owner could perform brute-force password guessing attack on other accounts efficiently…
Post: MySQL and the SSB - Part 2 - MyISAM vs InnoDB low concurrency
May 22, 2013 By Leave a Comment
… in memory, InnoDB almost always performs better, at least for this workload. Notes MySQL version used: 5.6.11, custom compiled to remove performance_schema For the InnoDB tests, a 64GB buffer pool was used. O_DIRECT was used so, there was no caching…_logs=32 innodb_old_blocks_time=0 table_open_cache=2048 table_definition_cache=16384 innodb_flush_method=O_DIRECT key_buffer…
Post: The write cache: Swap insanity tome III
April 19, 2013 By 5 Comments
Swapping has always been something bad for MySQL performance but it is even more important for HA systems. It … to interleave the allocation of memory for the MySQL process using the numactl utility, drop the file cache and pre-allocate the innodb… was especially puzzling since MySQL was not involved. The server was running with nearly 7GB of free memory but the push to…
Comment: Virident vCache vs. FlashCache: Part 1
May 17, 2013 By 3 Comments
… not Virident, but there’s a comparison in TPCC-MySQL performance between that card and a traditional SSD – the … to run in memory (not actual RAM, that’s true, but much closer to memory speed than a …. I’d never even heard of the STEC caching solution prior to your comment. Maybe another Perconian …
Post: Is Synchronous Replication right for your app?
May 14, 2013 By 18 Comments
… it with by fsyncing to memory (Battery or capacitor-backed write cache), etc., but the … MySQL replication from this instance, since MySQL replication is asynchronous. What about semi-sync MySQL replication…an lower bound on performance, only a upper bound. The best performance you can expect …
Post: Virident vCache vs. FlashCache: Part 2
May 17, 2013 By 3 Comments
… FlashCache performance versus that of vCache, and I also included a “no cache” test run as well using the base HDD MySQL configuration… available buffer pool memory but still fits into the cache device, vCache shines. Compared to a deployment with no SSD cache whatsoever, FlashCache…
Post: MySQL Server Memory Usage
May 17, 2006 By 21 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 28 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 …
