On 3/14/07, Clyde Lewis <[EMAIL PROTECTED]> wrote:
System Configuration: Sun Microsystems sun4u Sun Fire E2900
System clock frequency: 150 MHZ
Memory size: 65536 Megabytes
CPU: 12 @ 1200 MHz
I'm looking for a tool that will allow us to determine the max number
of databases that can run in a single instance of MySQL on a pretty
beefy server( Spec above).
In total we will have about ~40 MySQL
instances running on this server. Each instance of MySQL, there will
have between 30-60 individual databases supporting an OLTP
application. I know that there are no know internal limits that MySQL
have regarding the number of databases that can be created, but I
would like get my hands on a tool that can simulate the number of
databases and identify where we would potentially run into
performance issues.
As I mentioned above, your performance issues are going to come not
from the number of databases, but from (primarily) how well-designed
your database tables and queries are, and (secondly) how you configure
the mysql server(s).
One important factor to bear in mind is that with 40 separate MySQL
instances on the single 64GB server, you will have a maximum 1.6GB of
RAM per instance (excluding memory used by the O/S and other
applications). This will have to be divided up between the various
memory buffers (key_buffer, innodb_buffer_pool, etc.) allocated by
each mysql process, so you might want to reconsider if you really need
to run 40 separate mysql processes, or whether all the databases can
live in the same MySQL instance and thus probably make better use of
the available RAM.
With regards to stress-testing and benchmarking, two popular tools for
benchmarking MySQL servers are:
Super Smack: http://vegan.net/tony/supersmack/
Sysbench: http://sysbench.sourceforge.net/
We need to determine whether to have multiple
servers to support the ~40 instances or have all ~40 instances on the
same machine. Any help of ideas would be greatly appreciated with
this decision.
I would be inclined to have separate machines, rather than put
everything on one huge server. By spreading the data around, you are
reducing the risk if the one mega-machine were to become unavailable,
and also reducing resource contention (on the disks, CPU, RAM etc.).
-- Alex
--
MySQL General Mailing List
For list archives: http://lists.mysql.com/mysql
To unsubscribe: http://lists.mysql.com/[EMAIL PROTECTED]
