… point of iiBench problem is to measure the cost of index maintenance. This experiment isn’t measuring the cost of index maintenance… memory). The cost of querying this database will be 10 times higher with this partitioning, however since you’ll have to…://bazaar.launchpad.net/~mdcallag/mysql-patch/mytools/annotate/head%3A/bench/ibench/iibench.py) is that it measures query performance too, so…
Post: Testing Intel SSD 520
May 1, 2012 By 7 Comments
… strange small periodic drops. To better understand response time ranges, we need to switch to synchronous IO… synchronous IO varying amount of threads and with measurements every 1 sec to see how bad are … how does it affect MySQL performance, and I am going to run some MySQL workloads on these cards…
Post: Introducing new type of benchmark
February 25, 2012 By 16 Comments
…; NewOrder transactions Per Minute in tpcc-mysql). However, like Mark Callaghan mentioned in comments, response time is way more important metric to…. The time waiting in the queue is added to a total response time. As a result we measure 95% or 99% response times. What does it give to us? It allows to see: What is the response time we…
Post: Why you should ignore MySQL's key cache hit ratio
February 28, 2010 By 27 Comments
… that doesn’t help, though. Problem 2: Counters don’t measure time The reason you still can’t tell which server is… ratio is a waste of time! The Oracle folks arrived at this conclusion a long time before the MySQL world started to come… analysis, you need to measure elapsed time, not just the number of times something happens. In the absence of timing information, and if you…
Post: Modeling MySQL Capacity by Measuring Resource Consumptions
March 8, 2011 By 1 Comment
… has published for example is good for measuring scalability of the system as concurrency growths….take a look at procfs for MySQL process: root@ubuntu:/var/log/mysql# cat /proc/19018/stat 19018… 1 CONCURRENT_CONNECTIONS: 0 CONNECTED_TIME: 800 BUSY_TIME: 775 CPU_TIME: 49 BYTES_RECEIVED: 21847267 BYTES…
Post: MySQL on Amazon RDS part 1: insert performance
March 15, 2011 By 37 Comments
… Database Service (RDS) is a cloud-hosted MySQL solution. I’ve had some clients hitting performance… project, I thought it would be interesting to measure the single-threaded insert throughput as sysbench ran …mean that we were IO-bound the whole time waiting on fsync operations. But we didn’t…
Post: TPC-H Run on MySQL 5.1 and 6.0
April 10, 2008 By 16 Comments
… MyISAM tables which are not ACID complaint. Plus we only measured Power to keep things simple. We tested 10G and 100G…. Times are given in seconds. Ratio is MySQL 6.0 time divided by MySQL 5.1 time so if it is less than 1 MySQL 6… set cut-off time to 3 hours to give MySQL more time to complete the queries: Query MySQL 5.0.23 MySQL 6.0.4Ratio…
Post: Upgrading MySQL
January 5, 2010 By 23 Comments
… case fixing code to run on different MySQL version is taking a lot of time you may wish to create second QA… and measuring its capacity) Setting up the Slave(s) If you want to minimize downtime it is best to use MySQL Replication… them. You can often stage upgrades in time a bit so if something happens (like MySQL crashes) you have only one/few…
Post: Actively monitoring replication connectivity with MySQL's heartbeat
December 29, 2011 By 1 Comment
… the time threshold, then the SLAVE IO thread will disconnect and try to connect again. This means we now measure the connection time or latency, not the time without binary log events. We’re actively… to setup with negligible overhead: mysql_slave > STOP SLAVE; mysql_slave > CHANGE MASTER TO MASTER_HEARTBEAT_PERIOD=1; mysql_slave > START SLAVE; MASTER…
Post: How to Identify Bad Queries in MySQL
January 10, 2011 By 16 Comments
… duration the query executed for, which has been available in MySQL for years. This is necessary for determining whether a group… a cluster. One-second granularity (what you get in standard MySQL) might be enough precision for finding some cases of queries… analytical step. I have done it many times with simple awk scripts and various statistical measures. What do you think? Is there…
