… at what the server is doing. For example, in Percona Server we have microsecond-precision timestamps for log events. Edit: note that…, which has been available in MySQL for years. This is necessary for determining whether a group of queries completed in a cluster. One-second granularity (what you get in standard MySQL) might be enough precision for…
Post: Analyzing Slow Query Table in MySQL 5.6
February 18, 2013 By 1 Comment
… on the server. I read the logging code in MySQL 5.6.10 source, in file sql/log.cc. I discovered that they… and lock time as floating-point numerics to microsecond scale: sql/log.cc, MYSQL_QUERY_LOG::write(): 1945 /* For slow query log…”, ulonglong2double(lock_utime)/1000000.0); However, just like in prior releases of MySQL, when writing slow query information to the log table…
Post: MariaDB 5.3 is released as GA!
March 5, 2012 By 17 Comments
… different) offer flexibility in schemas Microsecond time resolution for DATETIME and similar time-based types, as well as microseconds in SHOW PROCESSLIST Group commit… of these features are also available either in Percona Server or in the upcoming MySQL 5.6 in the same or slightly different forms…
Post: How Percona does a MySQL Performance Audit
November 24, 2008 By 17 Comments
…_tmp_tables and Created_disk_tmp_tables, I’ll paste in mysql> show global variables like ‘%table_size%’; +———————+———–+ | Variable_name | Value | +———————+———–+ | max… has the Percona patches for microsecond logging and additional information in the slow query log output. The stock MySQL server’s limitation of…
Post: MySQL 5.6: Improvements in the Nutshell
January 27, 2013 By 16 Comments
… for Percona MySQL University in Raleigh,NC, Tuesday 29th of January I have created the outline of improvements available in MySQL 5…. MemcacheD API in Innodb – Explicit Partition Selection in queries – Full Text Search index for Innodb – Microsecond TIME precision – Precise spatial operations in GIS…
Post: Guess what?! Microsecond slow query timing finally available in MySQL!
August 29, 2007 By 5 Comments
… 5.1.20 failed to apply correctly on the new MySQL release. Imagine the expression on my face after I unpacked… and found out that MySQL incorporated the patch to their release. So it’s a built-in feature now in the 5.1…
Post: The two even more fundamental performance metrics
May 5, 2011 By 6 Comments
…’s the essence of performance: understanding events at points in time. And in a system that accepts, processes, and replies to requests… a millisecond — maybe it’s 50 microseconds, maybe a bit longer. This is common in MySQL servers I work with when they’re running a simple read-mostly workload with most data in memory. If…
Post: How much overhead DRDB could cause ?
June 2, 2008 By 4 Comments
…” operations in MySQL 5.0 – there is event written to the binary log to “prepare” XA transaction, when there is record in Innodb… be 200 microseconds. With such case even considering extra overhead besides network IO we’re speaking about 300 microseconds vs 5000 microseconds and… logs are) – in this case you have about 100 microsecond for request execution while DRBD overhead remains at 200-300 microseconds for requests…
Post: Is your server's performance about to degrade?
May 18, 2010 By 13 Comments
… 5.0.84, so I have microsecond logging in the slow query log, and extended statistics in the same log. I logged a… NOW() that disable the query cache) are executing in no more than 12 microseconds, worst-case. So the contention that’s blocking… — and that’s where improvements to the MySQL source code are necessary. But in many cases something can be done, such as…
Post: Updated msl (microslow) patch, installation walk-through!
April 20, 2008 By 17 Comments
… -f – mysql-5.0.51a/ mysql-5.0.51a/bdb/ mysql-5.0.51a/bdb/Makefile.in mysql-5.0.51a/bdb/btree/ mysql-5.0… which of those you want to have in your slow log. For example to have microsecond query timing and InnoDB statistics you… microseconds to execute to file. This option is standard MySQL, however after you apply the patch, it will no longer take time in…
