MySQL Load - Failed to establish Database

[codegirl42]

Hoping someone can help me analyze this.
I have one site on the server that has extremely high MYSQL load.
The site seems to get a lot of "Failed to establish Database connection" errors when people are trying to access all at once. After a minute or two, the site will load again.

Any help would be greatly appreciated. Thanks so much.

Here's the output from the tuning primer script:
---------------------------------------------------------------------


/usr$ ./tuning-primer.sh
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified

 -- MYSQL PERFORMANCE TUNING PRIMER --
 - By: Matthew Montgomery -

MySQL Version 4.1.22-standard i686

Uptime = 181 days 20 hrs 37 min 25 sec
Avg. qps = 14
Total Questions = 223271032
Threads Connected = 4

Server has been running for over 48hrs.
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
It should be safe to follow these recommendations

To find out more information on how each of these
runtime variables effects performance visit:
http://dev.mysql.com/doc/refman/4.1/en/server-system-variables.html
Visit http://www.mysql.com/products/enterprise/advisors.html
for info about MySQL's Enterprise Monitoring and Advisory Service

SLOW QUERIES
The slow query log is NOT enabled.
Current long_query_time = 10 sec.
You have 1666 out of 223271055 that take longer than 10 sec. to complete
Your long_query_time may be too high, I typically set this under 5 sec.

BINARY UPDATE LOG
The binary update log is NOT enabled.
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
You will not be able to do point in time recovery
See http://dev.mysql.com/doc/refman/4.1/...-recovery.html

WORKER THREADS
Current thread_cache_size = 8
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
Current threads_cached = 6
Current threads_per_sec = 0
Historic threads_per_sec = 0
Your thread_cache_size is fine

MAX CONNECTIONS
Current max_connections = 500
Current threads_connected = 2
Historic max_used_connections = 73
The number of used connections is 14% of the configured maximum.
Your max_connections variable seems to be fine.

MEMORY USAGE
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
Max Memory Ever Allocated : 758 M
Configured Max Per-thread Buffers : 2 G
Configured Max Global Buffers : 426 M
Configured Max Memory Limit : 2 G
Physical Memory : 1.94 G

Max memory limit exceeds 90% of physical memory

KEY BUFFER
Current MyISAM index space = 92 M
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
Current key_buffer_size = 384 M
Key cache miss rate is 1 : 627
Key buffer fill ratio = 4.00 %
Your key_buffer_size seems to be too high.
Perhaps you can use these resources elsewhere

QUERY CACHE
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
Query cache is enabled
Current query_cache_size = 32 M
Current query_cache_used = 21 M
Current query_cache_limit = 1 M
Current Query cache Memory fill ratio = 68.61 %
Current query_cache_min_res_unit = 4 K
MySQL won't cache query results that are larger than query_cache_limit in size

SORT OPERATIONS
Current sort_buffer_size = 2 M
Current read_rnd_buffer_size = 256 K
Sort buffer seems to be fine

JOINS
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
Current join_buffer_size = 132.00 K
You have had 793425 queries where a join could not use an index properly
You have had 1292 joins without keys that check for key usage after each row
You should enable "log-queries-not-using-indexes"
Then look for non indexed joins in the slow query log.
If you are unable to optimize your queries you may want to increase your
join_buffer_size to accommodate larger joins in one pass.
Note! This script will still suggest raising the join_buffer_size when
ANY joins not using indexes are found.


[troxalias]

What is the server's overall load ? Could you please post your /etc/my.cnf file as well as an estimation of the concurrent users on the site ?

[codegirl42]

Hi,

Here is the etc/my.conf

[mysqld]
set-variable = max_connections=1000
set-variable = max_user_connections=500
set-variable = interactive_timeout=100
set-variable = wait_timeout=15
set-variable = connect_timeout=10
safe-show-database
key_buffer = 20M
max_allowed_packet = 16M
table_cache = 512
sort_buffer_size = 2M
read_buffer_size = 3M
myisam_sort_buffer_size = 64M
thread_cache = 128
query_cache_size = 100M
# Try number of CPU's*2 for thread_concurrency
thread_concurrency = 4
safe-show-database