Apache keeps crashing due to unable to create worker thread

Question

Am getting a lot of these in our error log

((11)Resource temporarily unavailable: apr_thread_create: unable to create worker thread) and (110)Connection timed out: proxy: HTTP: attempt to connect to 127.0.0.1:80 (*) failed

The parameters of the worker in httpd.conf are as follows

StartServers         8     
ServerLimit        128     
MaxClients         2048    
MinSpareThreads     25     
MaxSpareThreads     75     
ThreadsPerChild     32     
MaxRequestsPerChild  10000 

I have changed the stack size in limit.conf but still not helping , Can anyone please help me ?

Update 04/04/2011: After Working on this Issue We have changed the configure file to the following

StartServers         8 
ServerLimit        64  
MaxClients           2048 
MinSpareThreads     25 
MaxSpareThreads     75 
ThreadsPerChild     32 
MaxRequestsPerChild  0 
ListenBacklog 2048 

And the connection error to localhost disappear We had to set MaxRequestPerChild to zero and we changed number of user's processes in the limits.d/90-nproc.conf

*          soft    nproc     40000

Solution

See here for a good answer:

Apache2 is not starting my webserver