… the active server of a pair. The passive server has mysqld running and replicating from the active master. In theory, failing over is the simple matter of… that? What does that mean? In most of these high-availability solutions it means that mysqld is running on the standby server and that replication is not… long_query_time to 0 in order to log every query. (See part two for handling massive slow log volume.) The slow…
Comment: Testing the Micron P320h
April 16, 2013 By 7 Comments
…, Thanks. This is what I’m wondering too… The difference is so much significant especially considering with O_DIRECT the majority of the stuff what we expect file… mean the first generation IoDrive ever released ? I think specific model number would really help to understand it. What I also find interesting is… amazing. It is great to leave at times when amount of IO you can push to the storage on the single node is measured in Gigabytes…
Post: MySQL 5.6 Compatible Percona Toolkit 2.2 Released
March 25, 2013 By 2 Comments
…operation, and its tries and wait time between tries for all operations are …For example, there are two versions of the DBD::mysql Perl module that have…is running them. What‘s new in 2.2 is that, whereas this feature (specifically, the … at intervals. Now –no-stalk means only that: don’t stalk, just …
Post: Introducing new type of benchmark
February 25, 2012 By 16 Comments
…5 is the mean of this random generation function. On the graph you see 20 events arrived within 9 seconds. Transactions from the …What is the response time we may expect having a given arrival rate What is the optimal number of working threads (the one that provides best response times) When it is…
Post: Identifying the load with the help of pt-query-digest and Percona Server
December 29, 2011 By 3 Comments
…(meaning 616.48K of data), however, 95% of the times InnoDB r ops is 0, which means it accesses these pages in memory. What it says though is …analysis of the query that is taking up the longest sum of run time, query ranked #1. The first row in the table above shows the Count of number of times this…
Post: Measuring the amount of writes in InnoDB redo logs
October 8, 2012 By 4 Comments
…time corresponding to operations recorded in the redo log What is not obvious from the documentation is that while Innodb_os_log_written is incremented when the…
Post: The Math of Automated Failover
September 18, 2012 By 9 Comments
… get the person to check what is going on and hit the button to initiate failover. Lets say automated failover is … numbers as much as 3-5 years as mean time between failures but lets be conservative. If it … Oct 1-2 and learn about many state of the art high availability solutions for MySQL such as …
Post: Flexviews - part 3 - improving query performance using materialized views
April 4, 2011 By 20 Comments
… This means that the minimum amount of drift for this type of MV is the amount of time it takes to execute the query on which the view is based.Â…at only what changed, even for MVs with aggregation and joins, is the value proposition for Flexviews. The flexviews.refresh() stored procedure The first …
Post: Enum Fields VS Varchar VS Int + Joined table: What is Faster?
January 24, 2008 By 30 Comments
… about 4 times faster than for MyISAM. This is great example of the case when Innodb is much faster than MyISAM for Read load. The other surprise could be almost zero cost of the join…; Result time(mean): 0.004170 As you can see, ENUM and VARCHAR results are almost the same, but join query performance is 30% lower…
Post: What does Handler_read_rnd mean?
June 15, 2010 By 15 Comments
…times, the storage engine API was called the handler API, which is why the variables begin with Handler_. Handler_read_rnd counts the number of times the…
