June 18, 2013

Post: More on MySQL transaction descriptors optimization

…-time=120 –max-requests=0 –percentile=99 –mysql-user=root –mysql-db=sbtest8t1M –mysql-table-engine=INNODB –mysql-socket=/tmp/mysql.sock –oltp-point-selects=1…-time=120 –max-requests=0 –percentile=99 –mysql-user=root –mysql-db=sbtest8t1M –mysql-table-engine=INNODB –mysql-socket=/tmp/mysql.sock –oltp-point-selects=9…

Post: Virident vCache vs. FlashCache: Part 2

…, 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…

Post: Testing the Micron P320h

… equally impressive; the next two graphs show 95th and 99th-percentile response time, but there really isn’t much difference between… latency just over 3ms. How well does it perform with MySQL? Exact results vary, depending upon the usual factors (read/write… compare the performance of the P320h on a standard TPCC-MySQL test to the original FusionIO and the Intel i910 with…

Post: Computing 95 percentile in MySQL

… doing performance analyzes you often would want to see 95 percentile, 99 percentile and similar values. The “average” is the evil of… response time goal in 95 or 99 percentile is much better. Say you say 99 percentile response time should be one second…/99 percentile and get your logs in the table, so how to get the data if MySQL only provides you the avg: mysql

Post: Evaluating IO subsystem performance for MySQL Needs

… should expect from the system. What I usually look for MySQL is performance in random reads and random writes. Sequential reads…: 0.0001s avg: 0.0001s max: 0.0086s approx. 95 percentile: 0.0001s Threads fairness: events (avg/stddev): 773835.0000/0….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

… this corresponds to pretty significant load. sysbench –test=oltp –mysql-user=root –mysql-password=”" –oltp-table-size=1000000 –num-threads=32 –init…: 0.68ms avg: 0.88ms max: 306.80ms approx. 95 percentile: 0.94ms …. We can see quite respectful performance with longest…: 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 ?

… 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… 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

…: 0.04ms avg: 0.06ms max: 0.34ms approx. 95 percentile: 0.06ms Threads fairness: events (avg/stddev): 1343.0000/0…: 0.10ms avg: 1.11ms max: 259.69ms approx. 95 percentile: 5.31ms Threads fairness: events (avg/stddev): 33900.0000/0…

Post: Identifying the load with the help of pt-query-digest and Percona Server

… enable logging atomically, not just for new connections as in MySQL. This is very helpful for measurement as otherwise we might… importance to the times/values reported in the 95% (95th percentile) column as that gives us more accurate understanding. Now, for… underlying tables involved and the query execution plan used by MySQL. The end result might be that you end up limiting…

Post: What do we optimize with mk-query-digest ?

… 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…