Migration from DB2 to Mysql - loss of performance
Dear Colleagues,
We migrated from DB2 to Mysql to test but we had a great loss of performance on our system.
Even running the server application where the database is, the slowness persists.
Did anyone migrate to Mysql and have a problem?
We are using the latest versions of Mysql ODBC and server.
Re: Migration from DB2 to Mysql - loss of performance
you need to better define slow?
maybe [URL="https://dev.mysql.com/doc/refman/8.0/en/optimization-indexes.html"]this[/URL] will help? I know there must be 'tweaks' you can make to the DB, but I don't know what they are on mySQL.
Re: Migration from DB2 to Mysql - loss of performance
MySQl has many tweaks available. Most all are done through My.ini, but it's something of a black art.
Unfortunately, MySQL is mostly used for small DBs and the issues we find in a big one (the one I work with is 60GB) are seldom discussed online. While DBAs for other DBs are readily available for hire, MySQl seems to be much tougher.
Re: Migration from DB2 to Mysql - loss of performance
With a DB that large you're going to want a screaming machine with an enormous amout of RAM and the fastest storage you can get. Without a large RAM cache, a database that large will be slow. The more of the database that can live in RAM, the faster it'll perform. It's always the thrashing to/from storage that slows things down.
Re: Migration from DB2 to Mysql - loss of performance
He never said how large his DB is. I talked about mine & we have tolerable performance with a 60GB DB on a 32GB server & ~150 users. We use a different driver though.
Re: Migration from DB2 to Mysql - loss of performance
Sorry Garret,
I was too busy multitasking (or failing to) and replied at the wrong point. MySQL (also known as MariaDB) can scale to petabytes. It's a similar layout to DB2.
BTW, how many transactions to you generate a day on the large system?
Best regards,
Eric
Re: Migration from DB2 to Mysql - loss of performance
Never counted. Million? More?
Scale MySQL to petabytes? Excuse my french, but NFW based on my experience on this system.
Re: Migration from DB2 to Mysql - loss of performance
I had a fairly big MySQL database for a customer. They had a top of line server with 64GB of RAM and fast drives. Number of users was not an issue. I spent a lot of time tuning the database. At the time I used MonYog which provided loads of tips on how to get the most out of the server and MySQL. Here's a [URL="https://webyog.com/"]link [/URL]to the company with their latest tools.