…) memory allocation is an costly operation and if memory allocator has scalability problems (like allocator from glibc) this will notably slowdown MySQL-transaction… memory during the entire connection lifetime and free it at disconnect. If some transactions require a larger amount of memory – we just reallocate memory… test for glibc and jemalloc allocators. Observations: = MySQL 5.5.30 – throughput of MySQL 5.5.30 with glibc is limited first…
Post: Memory allocators: MySQL performance improvements in Percona Server 5.5.30-30.2
April 15, 2013 By
Post: trx descriptors: MySQL performance improvements in Percona Server 5.5.30-30.2
April 12, 2013 By 3 Comments
… states is then a matter of copying a relatively small memory block which, depending on many factors, can be from few… to the following kinds of transactions: MySQL transactions started with START TRANSACTION READ ONLY MySQL transactions created by a non-locking SELECT… requires neither read-only server nor rewriting application queries. Furthermore, it can be combined with the read-only optimization in MySQL 5…
Post: Is Synchronous Replication right for your app?
May 14, 2013 By 18 Comments
…_commit != 1), or work around it with by fsyncing to memory (Battery or capacitor-backed write cache), etc., but the principle… no effect on standard MySQL replication from this instance, since MySQL replication is asynchronous. What about semi-sync MySQL replication? It’s actually… distributed system requires tradeoffs. Most of us are used to the tradeoffs we take when deploying conventional stand-alone MySQL Innodb with…
Post: Virident vCache vs. FlashCache: Part 1
May 16, 2013 By 3 Comments
… to conduct some benchmarks for the use case where the MySQL working set is significantly larger than the InnoDB buffer pool…. FlashCache, on the other hand, requires building a separate kernel module in addition to whatever flash memory driver you’ve already had to install, and then further configuration requires modification to assorted sysctls…
Post: Virident vCache vs. FlashCache: Part 2
May 17, 2013 By 3 Comments
…pre-release modules I received from Virident required the use of the CentOS 6.2… working set outstrips the available buffer pool memory but still fits into the cache device,…requests=0 –percentile=95 \ –mysql-user=root –mysql-socket=/tmp/mysql.sock –mysql-table-engine=innodb \ –oltp-…
Post: Profiling MySQL Memory Usage With Valgrind Massif
January 9, 2013 By 3 Comments
… memory profile slowly growing overtime, indicating a possible memory bug. Whatever the reason, there is a simple but powerful way to profile MySQL memory… options to match the snapshot frequency etc. to your specific requirements. However, you’ll likely find that the default options will…
Post: MySQL Server Memory Usage
May 17, 2006 By 21 Comments
… be impractical. Here is why: List of rarely considered MySQL Server Memory Requirements Thread buffers can be allocated more than once for each… Engine. This may have unbound memory requirements retriving result sets from remove queries. Blobs may require 3x time of memory. This is important if…
Post: How to Monitor MySQL with Percona's Nagios Plugins
February 22, 2012 By 11 Comments
… down for a system reboot. The pmp-check-mysql-pidfile plugin verifies that MySQL‘s PID file exists. Evidence of contention in…-unix-memory plugin checks for a single process consuming too much memory and/or for too little free memory in general. This plugin requires… of fixed-size connection pooling, for example, which can sometimes require application downtime to resolve), then it might be worth considering…
Post: Modeling MySQL Capacity by Measuring Resource Consumptions
March 8, 2011 By 1 Comment
… take a look at procfs for MySQL process: root@ubuntu:/var/log/mysql# cat /proc/19018/stat 19018 …this information is to compare systems with different memory amount having same workload. You will often … time spent. This is because IO handling requires significant number of CPU. With Percona Server, …
Post: Shard-Query EC2 images available
May 11, 2011 By 2 Comments
… 64 bit varieties. Due to memory requirements, the InnoDB versions are only available on 64 bit instances. MySQL will fail to start on…-64bit x86_64 Percona Server 5.5.11 with XtraDB. Requires m1.large or larger. ami-f65ea19f shard-query-infobright-demo i686 ICE 3.5.2pl1 32bit. Requires m1.small or greater. snap-073b6e68 shard-query-demo-data…
