MySQL Error: Can't create a new thread (errno 11); if you are not out of available memory

Recently I have met a big trouble in one of my newly migrated server.When ever mysql reached 1005 connections it throws a below error,

mysql error: Can't create a new thread (errno 11); 

if you are not out of available memory, you can consult the manual

for a possible OS-dependent bug 

So I have checked the mysql max_connections,open_file_limit and ulimit.Everything looks fine But still i got the same error.I was googled  and found a solution for it.This error depend upon OS not from MySQL.

So when I checked my  max user processor and open files by using ulimit -a I have seen these two variable has 1024 only so I have increased the max user processor and open files value in server.



Then restarted MySQL.


Now its fixed..

VARIABLES TO BE TUNE FOR MYSQL OPTIMIZATION

Here, I gave the list of variables to be tune for MySQL optimization. And give the value for each variable belongs to your system  configuration.

The MySQL server

#mysqld

max_connections

max_user_connections

key_buffer_size

myisam_sort_buffer_size

bulk_insert_buffer_size

join_buffer_size

read_buffer_size

sort_buffer_size

table_cache

table_open_cache

thread_cache_size

max_heap_table_size

tmp_table_size  

interactive_timeout

wait_timeout

connect_timeout

max_allowed_packet

max_connect_errors

query_cache_limit

query_cache_size

query_cache_type

log_slow_queries

long_query_time 

#InnoDB tables

innodb_log_buffer_size

innodb_buffer_pool_size

innodb_additional_mem_pool_size

#mysqldump

max_allowed_packet

#myisamchk

key_buffer_size

sort_buffer_size

read_buffer_size