… and then the new partition starts getting too big, so Inno starts slowing down again. The …55GB RAM, Inno would hit a memory wall. Given that Memory sizes are perhaps 10 times bigger than…that Mark wrote http://bazaar.launchpad.net/~mdcallag/mysql-patch/mytools/annotate/head%3A/bench/ibench/iibench….
Post: Multi Range Read (MRR) in MySQL 5.6 and MariaDB 5.5
March 21, 2012 By 10 Comments
… MySQL 5.6, when the workload fits entirely in memory, because there is no extra cost for memory access at random locations versus memory…_mrr_rowid_refills = 0, which means that the buffer was big enough and only 1 MRR range scan was needed, which…-memory, in fact MRR adds extra sorting overhead which means that the queries are just a bit slower as compared to MySQL…
Post: Ultimate MySQL variable and status reference list
January 8, 2011 By 4 Comments
… the amazing MySQL manual, especially the option and variable …idblogpercona.commanual shared_memoryblogpercona.commanual shared_memory_base_nameblogpercona.commanual show_slave_auth…auto_is_nullblogpercona.commanual sql_big_selectsblogpercona.commanual sql_big_tablesblogpercona.commanual sql_…
Post: Disaster: MySQL 5.5 Flushing
September 18, 2011 By 27 Comments
… memory much faster than on disk. InnoDB is not able to catch up with flushing changed data. With widely adoption of MySQL 5.5 and servers with big memory configuration I expect we will see this problem… modern hardware with a lot of memory. I hope there is work in progress for MySQL 5.6. Scripts and raw results…
Post: Helgrinding MySQL with InnoDB for Synchronisation Errors, Fun and Profit
November 24, 2011 By 2 Comments
… related to multithreading–deadlocks, data races, starvations etc–have a big impact on application’s stability and are at the same… the waiters field next, the read must be serialized in memory after the reset. A speculative processor might perform the read…, I’d consider backporting and using MySQL 5.5 atomic operation primitives with proper memory barriers, so that there is no need…
Post: MySQL on Amazon RDS part 1: insert performance
March 15, 2011 By 37 Comments
Amazon’s Relational Database Service (RDS) is a cloud-hosted MySQL solution. I’ve had some clients hitting performance limitations on… instance, which is listed as “High-Memory Quadruple Extra Large DB Instance: 68 GB of memory, 26 ECUs (8 virtual cores with…. This creates a table+index data size approximately twice as big as memory, so the workload should be somewhat IO-bound. My…
Post: Three ways that the poor man's profiler can hurt MySQL
December 2, 2011 By 19 Comments
… profiler has become a key tool in helping us analyze MySQL when customers are having trouble. We have our own implementation…’s usually a couple of seconds, but on big servers with a lot of memory and many threads, it can take much… they can be. Of course, I’m really waiting for MySQL 5.6 and the improved Performance Schema that will be…
Post: How Percona does a MySQL Performance Audit
November 24, 2008 By 17 Comments
…box’s hardware, including RAID controllers, installed memory, and so on in the boot output. …mysql –user=mysql –pid-file=/var/run/mysqld/mysqld.pid –skip-external-locking –port=3306 –socket=/var/db/mysql/mysql…bad that can be fixed and bring big gains. Schema, query, and index optimization …
Post: Side load may massively impact your MySQL Performance
November 13, 2011 By 7 Comments
… we run tests concurrently because Sysbench should run completely in memory and use a lot of CPU resources but none of…-driver=mysql –mysql-host=localhost –mysql-table-engine=innodb –mysql-db=test –oltp-table-name=md_cache_test_big –oltp-table-size=17600000 –mysql-user=msandbox –mysql…
Post: MySQL performance on EC2/EBS versus RDS
August 4, 2011 By 10 Comments
… overview of these two approaches to hosting MySQL in the Amazon cloud. In general, MySQL performance overall on EC2 and EBS isn… doesn’t always work, and it relies on memory, which only goes so big in the Amazon cloud. And you’re on…. The physical and logical database design influences greatly how much memory and disk resources are required. The application’s access patterns…
