FastCGI errors after timeout

We been using FastCGI (mod_fastcgi) for a year and it has been working 
great. Recently and without configuration changes, we've experienced a 
problem.

After a "timeout" condition (a transaction exceeded the 30-sec limit), 
successive transactions caused FastCGI "failed to connect to server" 
errors in the apache error_log, and eventually the CGI processes 
starting to die after the first execution. After an apache graceful 
restart, the problem goes away until the timeout occurs again.

Anyone have this problem, solutions or suggestions?

Details:

We use FastCGI to invoke a Perl process to handle straightforward API 
calls to our system. This api-server process stays resident and 
persistent and holds onto database connections to remove the overhead of 
a large number of database connects and Perl runtime initialization.

The api-server itself is configured to self-end after 10 minutes of 
runtime, to keep things "fresh". FastCGI automatically starts another 
process when this occurs, and it all works wonderfully.

Due to other long-running database-related processes on the system, 
there comes a time where the PostgreSQL database becomes unresponsive 
for a period of about 4 minutes at a time. This is certainly not 
desirable, and we are also working to resove this issue.

However, when this occurs, the currently executing FastCGI transaction 
is blocked for the 4 minutes before it returns. The timeout of FastCGI 
is set to the default 30 seconds, and it detects the timeout condition. 
The following error messages result:

    [Thu Dec 16 22:06:56 2004] [error] [client xxx.xxx.xxx.xx]
    FastCGI: comm with (dynamic) server
    "/path/bl-api-server.fpl"
    aborted: (first read) idle timeout (30 sec)
    [Thu Dec 16 22:06:56 2004] [error] [client xxx.xxx.xxx.xx]
    FastCGI:incomplete headers (0 bytes) received from server
    "/path/bl-api-server.fpl"

After that each transaction encounters the same problem and occasionally 
this error:

    [Sun Dec 19 05:59:42 2004] [error] [client 207.218.164.32]
    (61)Connection refused: FastCGI: failed to connect to server
    "/path/bl-api-server.fpl": connect() failed
    [Sun Dec 19 05:59:42 2004] [error] [client 207.218.164.32]
    FastCGI: incomplete headers (0 bytes) received from server
    "/path/bl-api-server.fpl"

During this period, FastCGI keeps starting api-server processes which 
run the transacation successfully, but then disappear. It does not 
appear that the process is ending naturally, but I suspect there maybe 
in issue with the Perl interface to FastCGI in holding the connection to 
the parent process.

After an apache graceful restart, the problem goes away.

On inspection of the api-server logs, each transaction was properly 
started and successfully executed, most within a second each. The error 
message after the response problem cleared continued to appear although 
the process did finish normally and long before the timeout period. I am 
not certain if the result HTTP page response was properly sent, though I 
assume not from these messages.

We are currently running FreeBSD 4.6.2-RELEASE-p2, FastCGI verion 
mod_fastcgi-2.4.2,  Apache 1.3.26, Perl version 5.005_03, and Perl 
interface to FastCGI veriosn $CGI::Fast::VERSION='1.01';

Thanks,
Allen
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