This morning, I was very happy to go to my first TechEd. Between the 10 seminars, as I said yesterday, I started with SQL Server 2008R2/2012 performance, tuning and optimization session. The thing is that we had just one session for the whole day. I will not copy the presentation of the 2 speakers (Thomas LaRock and Denny Cherry) who presented remarkably this session despite the failure of air conditioning during the morning. Fortunately, it…
Data can be corrupted in different ways, for example an I/O issue when reading data from the storage or a memory issue when updating data. The db_block_checking parameter allows to change the behavior of an Oracle database concerning block checking.
This posting will present this parameter and some tests to measure its impact on the database.
Who never had to measure the disk performances on a system?
Speaking about Linux performance monitoring includes a significant part on disk performances. If you are facing applications or databases running slower than expected or than on other environments, you may take a look on the I/O performances.
This blog aims to provide to introduction to a pretty interesting tool, iozone…
Last week, Oracle Ace Director Jonathan Lewis held an Oracle Optimizer Workshop at dbi services BaselArea. I would like to share some of the key learnings of this really interesting exchange I experienced together with my colleagues.
I’m pretty sure that most of you already struggled with some low performance systems. In order to analyse such cases several tools and utilities, like top, nmon, fuse or lsof are available under Linux. However trying to dig in processes analysis and looking for files and processes relations may be quite painful.
To get started with performance checks and analysis, a interesting utility is available: htop
I have seen at a customer that the SQL Server’s policy doesn’t follow the Microsoft’s recommendations about antivirus and databases(kb 309422), such excluding *.mdf,*.ndf and *.ldf files. In addition the policy for Oracle doesn’t exist in case of Forefront Endpoint Protection 2010 known as FEP 2010.
I have decided to create databases policies for FEP optimized by dbi services to be generic and adapted to all SQL Server and Oracle environments.
Sometimes, you need to modify the statistics of a table. There are various reasons: either for the performance analysis or because the execution plan changed. Oracle offers two methods: statistics restore or statistics export. Both are in the dbms_stats package. 1. Statistics restore This method uses the procedure dbms_stats.restore_%_stats, where % can be table, schema, database, and fixed_objects. This is an example for a restoration of a table with definite timestamp. The starting situation is:…
Nowadays MySQL Databases are encapsulated into many mission critical software solutions. Lots of companies host one or many MySQL databases in their data center, sometimes even without knowing it except when the MySQL service is no more available. In order to increase this service availability it is mandatory to have a monitoring solution. Regardles of you are using MySQL Server, MySQL replication or cluster the Oracle/MySQL monitoring solution is called MySQL Enterprise Monitor.