Recently I wrote about InnoDB scalability on 24-core box, and we made research of scalability problems in sysbench write workload (benchmark emulates intensive insert/delete queries). By our results the problem is in concurrency on rollback segment, which by default is single and all transactions are serialized accessing to segment. Fortunately InnoDB internally has mechanism to […]
One of our customers gave me a chance to run some benchmarks on 24-core (intel cpu based) server, and I could not miss it and ran few CPU-bound tasks there. The goal of benchmarks was investigation of InnoDB-plugin and XtraDB scalability in CPU-bound load.
As you likely have seen Sun has posted the new SpecJAppServer Results More information from Tom Daly can be found here These results are quite interesting for me as I worked on some of the previous SpecJAppServer Benchmarks several years ago while being employed by MySQL. These are great results, plus they can be relevant […]
Quite frequently I would log in to customers system and find MySQL using too much memory. I would look at memory consumed by Innodb (it is often higher than innodb_buffer_pool_size) substract memory used by other global buffers such as query_cache_size and key_buffer and will in many cases see some mysterous memory which I can’t really […]
During last couple of months I had number of consulting projects with MySQL Query Cache being source of serious problems. One would see queries both for MyISAM and Innodb tables mysteriously stalling for few seconds with “NULL” in State column. These could be troubleshooted to waiting on Query Cache which at the same time had […]
My favorite question during Interview for people to work as MySQL DBAs or be involved with MySQL Performance in some way is to ask them what should be tuned in MySQL Server straight after installation, assuming it was installed with default settings. I’m surprised how many people fail to provide any reasonable answer to this […]
Every so often people ask me the question how should they estimate memory consumption by MySQL Server in given configuration. What is the formula they could use. The reasons to worry about memory usage are quite understandable. If you configure MySQL Server so it uses too small amount of memory it will likey perform suboptimally. […]