CentOS release 6.8
innodb_buffer_pool_size = 50G
innodb_log_file_size = 2G
innodb_flush_log_at_trx_commit = 0
sync_binlog = 0
innodb_flush_method = O_DIRECT
innodb_buffer_pool_instances = 16
innodb_thread_concurrency = 16
skip_name_resolve = 1
innodb_io_capacity = 4000
innodb_io_capacity_max = 6000
innodb_buffer_pool_dump_at_shutdown = 1
innodb_buffer_pool_load_at_startup = 1
query_cache_size = 0
query_cache_type = OFF
innodb_checksum_algorithm = crc32
table_open_cache_instances = 16
innodb_read_io_threads = 20
innodb_write_io_threads = 10
max_connections = 700
when we have peaks of 3000 concurrent clients the mysqld does not seem
to pull all the resources posibles from the machine.
That reflects in the front end server
UPDATE After research the problem seem to be in the slow queries, so I
guess this configuration is optimal for this hardware
No, it is not likely to be a simple tuning change. As I said,
my.cnf looks good -- based on limited information.
Based on the charts, something happened suddenly. Or a flurry of activity.
Turn on the slowlog, set long_query_time=1, wait until the problem happens again, then use pt-query-digest to tell you the naughty query.