>>innodb_buffer_pool_size 12884901888 #12G
Since you have 12G innodb buffer pool, so I assume you have 16G RAM?
>1. Should I need to use multiple innodb_buffer_pool_instances?
At this stage no
>2. Should I need to use the innodb_flush_method=O_DIRECT
What file system are you using ext3?
>3. Should I need to increase the innodb_thread_concurrency?
Value for this option variable is '0' as per provided global variables data.
"A value of 0 (the default) is interpreted as infinite concurrency (no concurrency checking)"
http://dev.mysql.com/doc/refman/5.5/en/innodb-parameters.html#sysvar_innodb_thread_concurrency
Edited 1 time(s). Last edit at 06/26/2012 03:20AM by Aftab Khan.