Need your help on mysql my.cnf Mysql CPU usage is 67%

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1

I am running mysql 5.5.43 and have many sleep processes. But the big issue is extreme CPU usage that oscillates from 50 to 75% or more
I give you my my.cnf file that i have currently. Can you kindly suggest me what are the right parameters for a server with 128 GB Ram?
I dont have #innodb-log-file-size = 128M activated as when i try mysql wont start may be i need to flush logs?

[mysqld]
datadir=/var/lib/mysql
socket=/var/lib/mysql/mysql.sock
user=mysql

symbolic-links=0
thread_concurrency = 8
query_cache_size = 128M
query_cache_limit = 128M
thread_cache_size = 8
myisam_sort_buffer_size = 64M
read_rnd_buffer_size = 8M
read_buffer_size = 2M
sort_buffer_size = 2M
table_open_cache = 512
max_allowed_packet = 16M
key_buffer_size = 4840M
wait_timeout = 40
interactive_timeout = 40
max_connections = 300
long_query_time = 10

INNODB

innodb-flush-method = O_DIRECT
innodb-log-files-in-group = 2
innodb-flush-log-at-trx-commit = 1
innodb-file-per-table = 1
innodb-buffer-pool-size = 2456M
innodb_flush_log_at_trx_commit = 2
#innodb-log-file-size = 128M
[mysqld_safe]
log-error=/var/log/mysqld.log
pid-file=/var/run/mysqld/mysqld.pid

2

You cant just change “innodb-buffer-pool-size” or “innodb-log-file-size” in my.cnf and expect things to work. First “innodb-log-file-size” should be 1/4 of what you set for “innodb-buffer-pool-size”, e.g. if you set “innodb-buffer-pool-size” to 256MB then “innodb-log-file-size” should be 64MB.

Next, check this post how to properly change this settings - https://stackoverflow.com/questions/3927690/howto-clean-a-mysql-innodb-storage-engine/4056261#4056261. I would advise to read and try to understand, otherwise just changing this two values could lead to MySQL corruption.