…”. I have labeled each query as Q{FLIGHT_NUMBER}.{QUERY_NUMBER}. In general, each flight examines different time periods or different regions. The…. All OS caches are dropped at this time as well. These set of queries were tested on the SSB at SCALE FACTOR…!. MyISAM may be good for raw performance, but there are limitations which MyISAM imposes that are difficult to work with. MyISAM…
Post: Choosing a MySQL HA Solution - Post-Webinar Q&A
June 7, 2013 By Leave a Comment
… virtual machines tend to handle process scheduling and timing much differently than traditional hardware, and I’ve … This can be useful if you’re trying to limit the amount of data sent over the wire, …PRM simply attempt to connect and run a simple query, but it’s always possible to build something …
Post: High-load problems? Investigate them with 'pt-query-digest'
April 23, 2013 By 2 Comments
… server was hitting its capacity, or if there was another limiting factor in the workload that made it scale poorly. This… no run time data available, but at least you get a nice ranking of queries sorted by the number of times they appear… queries. To my luck, one query stood out right away, always appearing many times more than any other one during peaks. Rewriting that query…
Comment: MySQL caching methods and tips
March 27, 2013 By 5 Comments
… lately it behave strangely. Sometimes it load fine and anther time it wasn’t load at all. Checking the log file… saw lots of error in accessing Database. It said the query X was failed and database wasn’t available for few… the same times. Maybe my only solution is to code the PHP to use less query and limit it to only make query which…
Post: More on MySQL transaction descriptors optimization
April 26, 2013 By Leave a Comment
… list of transactions, its applicability is quite limited. Namely, it requires the list of transactions… of updates to the database, all SELECT queries, even those participating in read-only transactions,… –rand-type=uniform –forced-shutdown=1 –max-time=120 –max-requests=0 –percentile=99 –mysql-…
Post: trx descriptors: MySQL performance improvements in Percona Server 5.5.30-30.2
April 12, 2013 By 3 Comments
…depending on many factors, can be from few times to orders of magnitudes faster than a list…It requires neither read-only server nor rewriting application queries. Furthermore, it can be combined with the … better scalability while removing the read-only limitations. Let’s take a look at the following…
Post: MySQL 5.6 Compatible Percona Toolkit 2.2 Released
March 25, 2013 By 2 Comments
… shouldn’t have a problem finding queries to run and compare. pt-query-digest is simpler pt-query-digest 2.2 has fewer…, we re-focused it on its primary objective: analyzing MySQL query logs. So the ability to parse memcached, Postgres, Apache, and… run forever by default, so specify –iterations or –run-time to limit how long they run. There are more changes in addition…
Post: Percona Toolkit for MySQL Webinar Followup Questions
April 5, 2013 By 1 Comment
I didn’t have time to answer all of the questions during Wednesday’s MySQL … sometimes have limitations. For instance, you won’t be able to have access to the slow query log file, so pt-query-digest…. But as discussed during the webinar, you may miss some queries. Q: Can we get copies of the scripts used in…
Post: Identifying the load with the help of pt-query-digest and Percona Server
December 29, 2011 By 3 Comments
… the report because it matches –limit. # Scores: Apdex = 1.00 [1.0], V/M = 0.00 # Query_time sparkline: | _^ | # Time range: 2011-12-28… where this query was executed. Next the “Query_time distribution” section shows how this query times mostly, which you can see majority of the time lies… the report because it matches –limit. # Scores: Apdex = 1.00 [1.0], V/M = 0.00 # Query_time sparkline: | .^_ | # Time range: 2011-12-28…
Post: MySQL Query Cache
July 27, 2006 By 70 Comments
… block query cache for rather long time for large query caches, which might be unsuitable for online applications. Limited amount of usable memory – Queries are constantly being invalidated from query…
