Greetings friends,

I want to share with you a situation I have been watching to see if anyone has had a similar experience and could share the experience with the aim of finding an explanation for the situation.

First I start with say that my database server has the following characteristics:
CPU: Dual Xeon Hex (6) Core 2.53GHz Westmere H/T
Mem: 64GB DDR3
Disc: Intel X25-M MLC 80 GB (4)
OS: CentOS - 64 bit
MySQL: 5.5.33

The MySQL setting are:
init_connect=SET CHARACTER SET utf8

max_connections = 1000
wait_timeout = 30
thread_concurrency = 3
max_allowed_packet = 2M

#Slow Querys
#log-slow-queries = /var/log/mysqlslowq.log
#long_query_time = 5

query_cache_type = 1
query_cache_size = 72M
query_cache_limit = 72M
thread_cache_size = 84
table_cache = 2560
table_open_cache = 576

join_buffer_size = 38M
key_buffer_size = 768M
myisam_sort_buffer_size = 86M
sort_buffer_size = 5M
read_rnd_buffer_size = 15M
read_buffer_size = 5M

server-id = 1
expire_logs_days = 5
max_binlog_size = 100M


The situation is:

The point is that I keep daily the server behavior and have frequently observed major peaks occur in the processor usage, sometimes reaching 1500% above where memory is always in 3.5 Gb of consumption.

Could someone tell me the reason for this behavior and if indeed the configuration of MySQL is the most suitable for this server?

Thanks you very much for the information.