MySQL / Fusion IO Configuration Question
This is similar to the question I answered two months ago : MySQL using too much CPU

FusionIO tends to be CPU aggressive. You will have to fight back by


Tuning InnoDB


more read threads (innodb_read_io_threads), perhaps 16
more write threads (innodb_write_io_threads), perhaps 16
raising or lowering innodb_io_capacity to match IOPs of your FusionIO device
raise the Log Buffer (innodb_log_buffer_size) to 1G
raise the Log File (innodb_log_file_size) to 128M

Converting as much of your MyISAM to InnoDB as possible because changes to .MYD are cached in the OS memory rather than any MySQL buffers


I would also lower max_connections to 2000 unless you know for a certainty to will get over 4500 simultaneous DB Connections. If you really need 5000, upgrade the VM's RAM to 48GB.

Give it a Try !!!