Since you are running MySQL 5.5, you may want to consider configuring InnoDB to access multiple cores

Here are the settings you should be using

innodb_thread_concurrency sets the upper bound on number of concurrent threads that InnoDB can hold open. Best round number to set for this is (2 X Number of CPUs) + Number of Disks. UPDATE : As I learned firsthand from the Percona NYC Conference, you should set this to 0 in order to alert InnoDB Storage Engine to find the best number of threads for the environment it is running in.

innodb_concurrency_tickets sets the number of threads that can bypass concurrency checking with impunity. After that limit is reached, thread concurrency checking becomes the norm again.

innodb_commit_concurrency sets the number of concurrent transactions that can be committed. Since the default is 0, not setting this allows any number of transactions to commit simultaneously.

innodb_thread_sleep_delay sets the number of milliseconds an InnoDB thread can be dormant before reentering the InnoDB queue. Default is 10000 (10 sec).

innodb_read_io_threads and innodb_write_io_threads (both since MySQL 5.1.38) allocate the specified number of threads for reads and writes. Default is 4 and maximum is 64.

innodb_replication_delay imposes thread delay on a slave is innodb_thread_concurrency is reached.

Here are my past posts on MySQL 5.5 and activating multiple cores for InnoDB

• Jun 01, 2012 : I've got 16GB of ram, how should I configure MySQL Server?
• May 07, 2012 : MySQL Server Performance
• Apr 26, 2012 : Is the CPU performance relevant for a database server?
• Mar 16, 2012 : Using multiple cores for single MySQL queries on Debian
• Oct 07, 2011 : Should I use a storage engine other than MyISAM to optimise these tables or should I get better disks?
• Sep 20, 2011 : Multi cores and MySQL Performance
• Sep 12, 2011 : Possible to make MySQL use more than one core?

There are three(3) aspects you need to consider

ASPECT #1

You may find this astonishing but did you know that some older versions of MySQL can outperform newer versions ? You must tune MySQL 5.5 properly. In fact, InnoDB has new options introduced into the InnoDB Plugin.

I have earlier articles in the StackExchange on this

• Jul 16, 2012 : decreased performance of stored procedure when migrated from mysql server 5.0 to 5.5
• Feb 22, 2012 : MySQL 5.1 vs MySQL 5.5 (5.1 twice as fast)
• Nov 24, 2011 : Why mysql 5.5 slower than 5.1 (linux,using mysqlslap)
• Jun 19, 2011 : How do I properly perform a MySQL bake-off?

ASPECT #2

Looking at the my.ini, something caught my attention: you have innodb_thread_concurrency=10. That's a definite no-no, especially with MySQL 5.5. I say this because MySQL 5.x thrives on setting the innodb_thread_concurrency to 0. At Percona Live NYC 2011, Ronald Bradford explicit told me as I sat in the audience not to set this to any other value than 0. By setting it to zero, it lets InnoDB figure out the correct number of threads it needs create.

ASPECT #3

You need to activate multiple cores for InnoDB. MySQL 5.0/5.1 are not designed to use multiple cores. The InnoDB Plugin (from MySQL 5.1.38 has new options for doing so. Those options are fully present in MySQL 5.5. Such include

• innodb_read_io_threads
• innodb_write_io_threads
• innodb_io_capacity