Our Magento store running on 1.9.x is using Percona MySQL server 5.6.29 and since our site generates loads of MySQL queries, I need caching as much as possible. I have configured my.cnf like this

```
# The server defaults are faster for transactions and fast SELECTs.
# Adjust sizes as needed, experiment to find the optimal values.
# join_buffer_size = 128M
# sort_buffer_size = 2M
# read_rnd_buffer_size = 2M
datadir=/var/lib/mysql
socket=/var/lib/mysql/mysql.sock

explicit_defaults_for_timestamp = 1
skip-name-resolve
innodb_file_per_table
innodb_thread_concurrency = 26
query_cache_size = 512M
query_cache_limit = 18M
thread_cache_size = 64
key_buffer_size = 512M
max_allowed_packet = 64M
table_open_cache = 2000
sort_buffer_size = 4M
read_buffer_size = 4M
read_rnd_buffer_size = 2M
myisam_sort_buffer_size = 64M
max_heap_table_size = 1024M
tmp_table_size = 1024M
query_cache_type = 1
wait_timeout = 300
max_connections = 200
innodb_buffer_pool_size = 64G
innodb_buffer_pool_instances=125
innodb_log_buffer_size=18M

# Disabling symbolic-links is recommended to prevent assorted security risks
# symbolic-links=0

# Recommended in standard MySQL setup
# sql_mode=NO_ENGINE_SUBSTITUTION,STRICT_TRANS_TABLES

# Slow Query
slow_query_log=1
slow_query_log_file=/var/log/mysql_slow_queries.log

[mysqld_safe]
log-error=/var/log/mysqld.log
pid-file=/var/run/mysqld/mysqld.pid

```

Our database size is just 6GB and machine has 120GB of RAM, so I need caching as much as possible to make things quicker. So, does the above configuration fits for BEST caching or is there any value I need to tune or add into?