… or certain times. Investigating them we find out what the cause is some batch jobs, reports and other non response time critical activities… problem, might be even not problem with your MySQL configuration, queries and hardware, even though fixing these does help in many… you put too heavy of concurrent load on it the response times will increase and user experience will suffer. So what you…
Post: Introducing new type of benchmark
February 25, 2012 By 16 Comments
… ready. 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 may expect having… session, affect a response time of queries that handle user load ? The same for mysqldump, how does it affect short user queries ? In fact…
Comment: Introducing new type of benchmark
February 26, 2012 By 16 Comments
… your 9x percentile response time performance until you use it against your work load with your dataset with your queries; thats what I… benefit immediately in terms of those incremental schema changes or query changes instead of a tool to gage scaling limitations of… apples there. I did dick around with proxy a long time ago and recall I ran into some problems under high…
Post: Troubleshooting MySQL Memory Usage
March 21, 2012 By 3 Comments
…understand which of the applications were responsible for memory allocation. If you figured… MEMORY tables which are allocated for query execution, which size can be …: 16384 INDEX_LENGTH: 0 CREATE_TIME: NULL UPDATE_TIME: NULL *************************** 2. row *************************** SESSION_ID:…
Post: Query Response time histogram - new feature in Percona Server
July 11, 2010 By 11 Comments
… of queries response times into Percona Server, and our software engineer Oleg Tsarev implemented this feature. The feature adds new INFORMATION_SCHEMA table QUERY_RESPONSE_TIME ( full docs are on page response_time_distribution), which looks like time count 0.000001 53 0…
Post: What do we optimize with mk-query-digest ?
December 15, 2009 By 2 Comments
… time which you can see which are unrelated to query itself – general system overload, row level locks, table locks all could cause query response time to be unreasonable. If Slowest query is not interactive query…
Post: Shard-Query turbo charges Infobright community edition (ICE)
May 6, 2011 By 22 Comments
… query features like BETWEEN or IN. It is also possible to spread your data over multiple machines, scaling out to improve query response times significantly. These queries are a great test of Shard-Query features. It is currently approaching RC…
Post: Shard-Query EC2 images available
May 11, 2011 By 2 Comments
… impact in our query response times and throughput. Setting up a cluster using the AMI images You can easily test Shard-Query for yourself… first number is wall time, the second exec time, the third parse time). $ echo “select count(*) from ontime_fact;” | ./run_query Array ( [count(*)] => 135125787…-packet=1M net-buffer-length=16K #we value throughput over response time, get a good plan optimizer-prune-level=0 partition=ON…
Post: Introducing tcprstat, a TCP response time tool
August 31, 2010 By 12 Comments
… information about the response time of the requests within that time period. Here “response time” means, for a given TCP connection, the time elapsed from the… HTTP and MySQL, this is the moral equivalent of a query‘s response time. The statistics we chose to output by default are the count, median, average, min, max, and standard deviation of the response times…
Post: Optimizing slow web pages with mk-query-digest
April 7, 2011 By 14 Comments
… response time for some random user requests, you are usually interested in queries that are consuming most MySQL time and that’s how mk-query… default. Fixing top 10 queries on the list indeed will most likely reduce the load and improve response time for some requests. What… impact to this page response time. I can also convert that into a slow query log that lists all the queries that were executed…
