… log, FRM files, MySQL MyISAM system tables etc. Starting MySQL 5.5 MySQL uses asynchronous IO which should allow it to load IO subsystem very effectively… Platform | Linux Release | Ubuntu 12.04.1 LTS (precise) Kernel | 3.2.0-35-generic Architecture | CPU = 64-bit, OS = 64-bit… Read_Ahead which is not available in MySQL 5.5 (different version is added back in MySQL 5.6) so I tried that as well…
Post: More Gotchas with MySQL 5.0
July 27, 2007 By 23 Comments
… MySQL 5.0 and doing oprofile analyzes we found very interesting issue of buf_get_latched_pages_number being responsible for most CPU… higher for MySQL 5.0 compared to MySQL 4.1 It was something like 2-3 for MySQL 4.1 vs 40-60 for MySQL 5.0 At the same time however there were virtually no disk IO and CPU being loaded…
Post: High Rate insertion with MySQL and Innodb
January 7, 2011 By 17 Comments
… 275K inserts/sec at which time we started to see load to get IO bound because of log writes and flushing… ? First MySQL 5.5 (frankly I did not try Percona Server 5.1 in this case) With MySQL 5.1 and Innodb Plugin we could see 40%+ CPU wasted on mutex spinlocks (per oprofile), which went down to about 15% in MySQL 5.5…
Post: Helgrinding MySQL with InnoDB for Synchronisation Errors, Fun and Profit
November 24, 2011 By 2 Comments
… of goodies does Helgrind find on MySQL server. Let’s take a recent 5.1 bzr version (pre-5.1.61) and a single test… word stores/loads are technically atomic, i.e. you cannot observe any intermediate state, it is likely that if other CPU cores… not-so-minor. Additionally, I’d consider backporting and using MySQL 5.5 atomic operation primitives with proper memory barriers, so that there…
Post: MySQL Users Conference - Innodb
May 9, 2007 By 6 Comments
…not yet know answer for – for example will LOAD DATA INFILE be optimized same way as for…multiple cores becomes increasingly important as their number per CPU just keeps doubling. It is also rather interesting… out where already which may come in MySQL 5.2 or even MySQL 5.1. I surely would like to see…
Post: Auditing login attempts in MySQL
December 28, 2012 By 4 Comments
…loaded…5.5 userstat = 1 5.1 userstat_running = 1 Then we get the information about a particular user: mysql> select * from user_statistics where user=’root’\G *************************** 1…
Post: Heikki Tuuri Innodb answers - Part I
October 26, 2007 By 19 Comments
…: Cool. This is one of little known new features in MySQL 5.1 Q15: How frequently does Innodb fuzzy checkpointing is activated HT… 200) for additional throughput? HT: ha_innodb.cc in 5.1: static MYSQL_SYSVAR_ULONG(thread_concurrency, srv_thread_concurrency, PLUGIN_VAR_RQCMDARG…: If your load is CPU bound and you’re scaling out you can get better performance by using couple of MySQL Servers on…
Post: InnoDB compression woes
May 20, 2011 By 14 Comments
… setup: Dell PowerEdge R900, running Percona-Server-5.1.57-rel12.8 (will be in public …CPU-bound benchmark. First stage – load data. Scripts for multi-table sysbench allow to load data in parallel, so let’s load…=0 –rand-type=uniform –max-time=1800 –mysql-user=root –report-interval=10 run this…
Post: Identifying the load with the help of pt-query-digest and Percona Server
December 29, 2011 By 3 Comments
…not just for new connections as in MySQL. This is very helpful for measurement…pt-query-digest can be pretty CPU and memory consuming, so ideally you…options # 8 0x4C16888631FD8EDB 0.1160 1.4% 5 0.0232 1.00 0.00 SELECT film…load. Now let’s take a look at the most important part of the output: # Query 1…
Post: Side load may massively impact your MySQL Performance
November 13, 2011 By 7 Comments
…load and many things can be happening concurrently. It is very typical to hear complains about MySQL…CPU to spare. We’re using Percona Server 5.5… correspond to 1 sec. Separate …MySQL 5.6 as it would offer much better “out of box” user experience. Summary As we can see in default configuration MySQL…
