DB Connection Fail

I stuck with problem, My database mysql server giving frequently error DB : connection fail
i tried almost all thing but then also in a day 10-12 time its give this error.
I had Separate database server than web server with 16 GB RAM server with high speed server

This is MY database server variable configuration,

Variable name 	Current value	auto_increment_increment 	1	auto_increment_offset 	1	automatic_sp_privileges 	ON	back_log 	50	basedir 	/usr/	bdb_cache_size 	8388600	bdb_home 	/lib/mysql/	bdb_log_buffer_size 	1036288	bdb_logdir 		bdb_max_lock 	10000	bdb_shared_data 	OFF	bdb_tmpdir 	/tmp/	binlog_cache_size 	32768	bulk_insert_buffer_size 	8388608	character_set_client 	latin1		character_set_connection 	latin1	character_set_database 	latin1	character_set_filesystem 	binary	character_set_results 	latin1	character_set_server 	latin1	character_set_system 	utf8	character_sets_dir 	/usr/share/mysql/charsets/	collation_connection 	latin1_swedish_ci	collation_database 	latin1_swedish_ci	collation_server 	latin1_swedish_ci	completion_type 	0	concurrent_insert 	1	connect_timeout 	10	datadir 	/lib/mysql/	date_format 	%Y-%m-%d	datetime_format 	%Y-%m-%d %H:%i:%s	default_week_format 	0	delay_key_write 	ON	delayed_insert_limit 	100	delayed_insert_timeout 	300	delayed_queue_size 	1000	div_precision_increment 	4	engine_condition_pushdown 	OFF	expire_logs_days 	0	flush 	OFF	flush_time 	0	ft_boolean_syntax 	+ -><()~*:""&|	ft_max_word_len 	84	ft_min_word_len 	4	ft_query_expansion_limit 	20	ft_stopword_file 	(built-in)	group_concat_max_len 	1024	have_archive 	NO	have_bdb 	YES	have_blackhole_engine 	NO	have_compress 	YES	have_crypt 	YES	have_csv 	NO	have_dynamic_loading 	YES	have_example_engine 	NO	have_federated_engine 	NO	have_geometry 	YES	have_innodb 	DISABLED	have_isam 	NO	have_merge_engine 	YES	have_ndbcluster 	NO	have_openssl 	DISABLED	have_query_cache 	YES	have_raid 	NO	have_rtree_keys 	YES	have_symlink 	YES	init_connect 		init_file 		init_slave 		innodb_additional_mem_pool_size 	1048576	innodb_autoextend_increment 	8	innodb_buffer_pool_awe_mem_mb 	0	innodb_buffer_pool_size 	8388608	innodb_checksums 	ON	innodb_commit_concurrency 	0	innodb_concurrency_tickets 	500	innodb_data_file_path 		innodb_data_home_dir 		innodb_doublewrite 	ON	innodb_fast_shutdown 	1	innodb_file_io_threads 	4	innodb_file_per_table 	OFF	innodb_flush_log_at_trx_commit 	1	innodb_flush_method 		innodb_force_recovery 	0	innodb_lock_wait_timeout 	50	innodb_locks_unsafe_for_binlog 	OFF	innodb_log_arch_dir 		innodb_log_archive 	OFF	innodb_log_buffer_size 	1048576	innodb_log_file_size 	5242880	innodb_log_files_in_group 	2	innodb_log_group_home_dir 		innodb_max_dirty_pages_pct 	90	innodb_max_purge_lag 	0	innodb_mirrored_log_groups 	1	innodb_open_files 	300	innodb_support_xa 	ON	innodb_sync_spin_loops 	20	innodb_table_locks 	ON	innodb_thread_concurrency 	8	innodb_thread_sleep_delay 	10000	interactive_timeout 	28800	join_buffer_size 	131072	key_buffer_size 	56623104	key_cache_age_threshold 	300	key_cache_block_size 	1024	key_cache_division_limit 	100	language 	/usr/share/mysql/english/	large_files_support 	ON	large_page_size 	0	large_pages 	OFF	lc_time_names 	en_US	license 	GPL	local_infile 	ON	locked_in_memory 	OFF	log 	OFF	log_bin 	OFF	log_bin_trust_function_creators 	OFF	log_error 		log_queries_not_using_indexes 	OFF	log_slave_updates 	OFF	log_slow_queries 	OFF	log_warnings 	2	long_query_time 	10	low_priority_updates 	OFF	lower_case_file_system 	OFF	lower_case_table_names 	0	max_allowed_packet 	16776192	max_binlog_cache_size 	18446744073709551615	max_binlog_size 	1073741824	max_connect_errors 	10	max_connections 	200	max_delayed_threads 	20	max_error_count 	64	max_heap_table_size 	16777216	max_insert_delayed_threads 	20	max_join_size 	18446744073709551615	max_length_for_sort_data 	1024	max_prepared_stmt_count 	16382	max_relay_log_size 	0	max_seeks_for_key 	18446744073709551615	max_sort_length 	1024	max_sp_recursion_depth 	0	max_tmp_tables 	32	max_user_connections 	0	max_write_lock_count 	18446744073709551615	multi_range_count 	256	myisam_data_pointer_size 	6	myisam_max_sort_file_size 	9223372036854775807	myisam_recover_options 	OFF	myisam_repair_threads 	1	myisam_sort_buffer_size 	8388608	myisam_stats_method 	nulls_unequal	net_buffer_length 	16384	net_read_timeout 	30	net_retry_count 	10	net_write_timeout 	60	new 	OFF	old_passwords 	ON	open_files_limit 	4258	optimizer_prune_level 	1	optimizer_search_depth 	62	pid_file 	/var/run/mysqld/mysqld.pid	port 	1044	preload_buffer_size 	32768	prepared_stmt_count 	0	protocol_version 	10	query_alloc_block_size 	8192	query_cache_limit 	1048576	query_cache_min_res_unit 	4096	query_cache_size 	209715200	query_cache_type 	ON	query_cache_wlock_invalidate 	OFF	query_prealloc_size 	8192	range_alloc_block_size 	2048	read_buffer_size 	131072	read_only 	OFF	read_rnd_buffer_size 	262144	relay_log_purge 	ON	relay_log_space_limit 	0	rpl_recovery_rank 	0	secure_auth 	OFF	server_id 	0	skip_external_locking 	ON	skip_networking 	OFF	skip_show_database 	OFF	slave_compressed_protocol 	OFF	slave_load_tmpdir 	/tmp/	slave_net_timeout 	3600	slave_skip_errors 	OFF	slave_transaction_retries 	10	slow_launch_time 	2	socket 	/var/lib/mysql/mysql.sock	sort_buffer_size 	28311544	sql_big_selects 	ON	sql_mode 		sql_notes 	ON	sql_warnings 	OFF	ssl_ca 		ssl_capath 		ssl_cert 		ssl_cipher 		ssl_key 		storage_engine 	MyISAM	sync_binlog 	0	sync_frm 	ON	system_time_zone 	PDT	table_cache 	2024	table_lock_wait_timeout 	50	table_type 	MyISAM	thread_cache_size 	40	thread_stack 	262144	time_format 	%H:%i:%s	time_zone 	SYSTEM	timed_mutexes 	OFF	tmp_table_size 	1048576000	tmpdir 	/tmp/	transaction_alloc_block_size 	8192	transaction_prealloc_size 	4096	tx_isolation 	REPEATABLE-READ	updatable_views_with_limit 	YES	version 	5.0.27	version_bdb 	Sleepycat Software: Berkeley DB 4.1.24: (October 21, 2006)	version_comment 	Source distribution	version_compile_machine 	x86_64	version_compile_os 	redhat-linux-gnu	wait_timeout 	28800</pre>