In its "Insight" Research Report from October 2010 "Messages from Oracle OpenWorld 2010: Exadata Exceeds Expectation and MySQL Thrives", IDC Carl W. Olofson notes:
"Last but not least, Oracle announced the MySQL 5.5 release candidate, which solidifies the commitment the company has made to continuing the development and the independence of MySQL as an open source relational DBMS. This announcement came along with continued assurances that MySQL is and will remain autonomous. Nonetheless, useful MySQL intellectual property may find its way into other Oracle products, and Oracle's database development engineers will almost certainly lend their expertise to helping make MySQL better...
...MySQL users should take heart from the 5.5 release candidate and the ongoing[Read more...]
Mark Callaghan over at Facebook wrote a note recently about InnoDB disk IO counters in SHOW STATUS, with some extra things that he wanted to track. I posted a quick comment over there, but I thought this deserved it’s own write up.
MySQL 5.5’s PERFORMANCE_SCHEMA has had a fair bit written about it in terms of tracking synchronization point contention (mutexes etc.), but it currently tracks two orders within the wait class - these are /wait/synch and /wait/io.
Actually, allow me to detour first, it’s not clear from the documentation, though it is clear in the worklog. Each[Read more...]
Seeing as it looks like 5.5 is shortly about to go GA I thought I’d give it a run and see how well it works. The only way really to test it is to give it a bit of load and look for things which break. That I did with the 5.5.6-rc community rpms, compared to the 5.1 advanced rpms I usually run.
My colleagues, Ben and Peter, found a horrible problem which means that I can’t use this even for any real usage on my real servers. See: bug#57095 for all the gory details. Thanks to them both for finding the problem and then digging down and figuring out the real cause. Sometimes developers work a long way from the database so their errors don’t translate into something I can really look at in the database. They delved into the problem and then found the cause and a nice easy test[Read more...]
Internally MySQL uses various methods to manage (or, block) concurrent access to shared structures within the server - the most common being mutexes (or Mutual Exclusion locks), RW Locks, or Semaphores. Each have slightly different properties on how different threads are allowed to interact when trying to access these synchronization points.
There has been much written on the various hot spots in the server around these locking/blocking constructs over the past couple of years, so I won’t go further in to that here. See the excellent blogs from Mikael or Dimitri from within Oracle, or those from the likes of[Read more...]
Yesterday, Sept. 19, 2010 at the inaugural MySQL Sunday event at Oracle OpenWorld, we announced the MySQL 5.5 Release Candidate. The MySQL 5.5 release candidate helps improve the performance and scalability of applications across multiple operating environments, including Windows, Linux, and Mac. Enhancements include:Improved performance and scalability: