… or queries which cause the large portion of the load on the system but how do we know whenever …which are found and returned up to the top level MySQL part for processing are counted the Rows_examined remains …pt-query-digest very well as it reports not only average numbers but also the outliers.
Post: Investigating MySQL Replication Latency in Percona XtraDB Cluster
March 3, 2013 By 13 Comments
… the Sysbench load on DPE1. With concurrency of 32 this corresponds to pretty significant load. sysbench –test=oltp –mysql-user=root –mysql-password=”" –oltp… in average and the Maximum one. This tells me from data propagation standpoint the cluster is more sensitive to the load on… and average delay for those over 5ms and outliers going to half a second. From these results I read the side load…
Post: Death match! EBS versus SSD price, performance, and QoS
February 21, 2011 By 55 Comments
… name, and the following statistics for reads: MB/s, average concurrency, and average response time in milliseconds. The same statistics are repeated… behind it, the device wouldn’t be 100% utilized until average read concurrency reached 6 and write concurrency reached 3. One…’m averaging across large periods of time here, so you can’t really see it, but there are significant spikes of load…
Post: Scaling: Consider both Size and Load
July 13, 2010 By 5 Comments
… out of there. Some (minority?) vary the load independently or almost independently of data size. … (which is similar measures as users in average have certain amount of data each). Doubling … scalability. The Replication is perfect example in MySQL world. Slave executes replication stream in single …
Post: Goal driven performance optimization
December 22, 2008 By Leave a Comment
… load on the system. MySQL Log analyzes with Mk-Log-Parser is a very good start for a ways to generally optimize MySQL load on the system. Latency Goal is another breed. The system may not look loaded but some pages… you can see in this case during certain hours the average type of bad queries skyrockets and it becomes 90% or…
Post: Performance or Stability ???
April 1, 2011 By 16 Comments
…in our peak time. Because most systems have load based on something called “random arrivals” rather … the less outliers you have with the same average response time the better it is. The relationships…response time your application can tolerate. In the MySQL Benchmarks Vadim Posted we see there are a…
Comment: MySQL Server Memory Usage
September 1, 2006 By 21 Comments
… how do you determine the memory consumption per connection in average? This leads to the next question c. Can we have… 18:38:40 up 175 days, 2:56, 1 user, load average: 0.79, 1.00, 0.95 328 processes: 326 sleeping…/mysql.sock pid-file=/var/run/mysql/mysql.pid datadir=/db/disk2/mysql/data log-bin=/var/log/mysql/log log-slow-queries=/var/log/mysql…
Comment: Beware of MyISAM Key Cache mutex contention
January 12, 2010 By 10 Comments
… they experienced mysql crazy cpu loads since more than one year which lead every now and then(once a week average) real deadlocks with up to 120 load average, mysql… under monitoring all the parameters I could think of, and mysql processes showed in issue periods multiple copies of the same…
Comment: Beware of MyISAM Key Cache mutex contention
August 14, 2008 By 10 Comments
…, Opened_tables=133. 1. Two threads and one table, the average response time is about 143ms Thread1: access table t1 Thread2…_keycache | status | OK | +———————————+———-+———-+ 4 rows in set (0.02 sec) mysql> LOAD INDEX INTO CACHE lps.user_1,lps.user_2,lps…
Post: Thoughts on MySQL Replication
July 7, 2006 By 18 Comments
… 4 times if write load growth by only 50%. – Delays in replication MySQL replication is fast which means in average delay is small… data you’re accessing to be cached in memory by MySQL cache or OS cache. As slaves replicate the same data… replication ? Not really this is great solution which offers great MySQL Performance in many cases. It is good however to understand…
