…, I think vCache can be declared the clear winner. Base MySQL & Benchmark Configuration All benchmarks were conducted with the following: sysbench…-requests=0 –percentile=95 \ –mysql-user=root –mysql-socket=/tmp/mysql.sock –mysql-table-engine=innodb \ –oltp-read-only=off run The base MySQL configuration (configuration A…
Post: Computing 95 percentile in MySQL
November 28, 2008 By 5 Comments
When doing performance analyzes you often would want to see 95 percentile, 99 percentile and similar values. The “average” is the evil of… 95/99 percentile and get your logs in the table, so how to get the data if MySQL only provides you the avg: mysql… this system the 95 percentile is just over 5 sec (some 3 times more than the average) and 99% percentile is just a…
Post: Evaluating IO subsystem performance for MySQL Needs
March 5, 2008 By 23 Comments
… should expect from the system. What I usually look for MySQL is performance in random reads and random writes. Sequential reads…: min: 0.0001s avg: 0.0001s max: 0.0086s approx. 95 percentile: 0.0001s Threads fairness: events (avg/stddev): 773835.0000/0… avg: 0.0027s max: 0.0112s approx. 95 percentile: 0.0030s So we get about 3ms 95 percentile request time – not bad – all request…
Post: Investigating MySQL Replication Latency in Percona XtraDB Cluster
March 3, 2013 By 13 Comments
… this corresponds to pretty significant load. sysbench –test=oltp –mysql-user=root –mysql-password=”" –oltp-table-size=1000000 –num-threads=32 –init…: min: 0.68ms avg: 0.88ms max: 306.80ms approx. 95 percentile: 0.94ms …. We can see quite respectful performance with longest…: min: 0.69ms avg: 1.12ms max: 52334.76ms approx. 95 percentile: 0.97ms As we see there is a stall in…
Post: mysql-proxy, urgh performance and scalability ?
June 9, 2009 By 44 Comments
… 1 thread). MySQL per-request statistics: min: 1.31ms avg: 1.51ms max: 5.30ms approx. 95 percentile: 1.56ms Proxy+MySQL per-request statistics: min: 2.04ms avg: 2.86ms max: 6.44ms approx. 95 percentile: 4.30ms… consider if you want to run Query Analyzer with MySQL-proxy on your MySQL Enterprise setup. There is alternative – Dormando-proxy, which…
Post: Virtualization and IO Modes = Extra Complexity
March 21, 2011 By 12 Comments
…: min: 0.04ms avg: 0.06ms max: 0.34ms approx. 95 percentile: 0.06ms Threads fairness: events (avg/stddev): 1343.0000/0…: min: 0.10ms avg: 1.11ms max: 259.69ms approx. 95 percentile: 5.31ms Threads fairness: events (avg/stddev): 33900.0000/0…
Post: What do we optimize with mk-query-digest ?
December 15, 2009 By 2 Comments
… acceptable for interactive queries. It is best to look at 95 percentile “time” rather than slowest time for the queries as there… to be optimized. It helps if batch jobs use different MySQL user compared to the web site itself as it makes…) – it is however perfectly possible to get bad performance with MySQL responsible for large portion of response time without any slow…
Post: Performance Optimization and Six Sigma
June 7, 2010 By 6 Comments
… and not acceptable. So how are doing with this in MySQL (and general Web performance management) ? Not So good. In most… 95 percentile something like 1000 transactions will give more or less stable results in most cases. If we’re looking at 99 percentile…. I believe meeting 95 percentile response time every minute of the day is a lot harder than getting 99 percentile over 24 hours…
Post: Identifying the load with the help of pt-query-digest and Percona Server
December 29, 2011 By 3 Comments
… enable logging atomically, not just for new connections as in MySQL. This is very helpful for measurement as otherwise we might… give more importance to the times/values reported in the 95% (95th percentile) column as that gives us more accurate understanding. Now… underlying tables involved and the query execution plan used by MySQL. The end result might be that you end up limiting…
Post: Color code your performance numbers
June 2, 2010 By 4 Comments
… functions. We most likely would like to see some percentile numbers – 95 percentile or 99 percentile. The problem is computing these in SQL is… 3 seconds and anything over that will be considered unacceptable: mysql> select sum(wtime=1.0 and wtime=3.)/count(*)*100… before we get large number of yellow or red requests: mysql> select avg(if(wtime
