Why does the broker print the following message "Could not accept socket: Too many open files (qpid/sys/posix/Socket.cpp:220)" in Red Hat Enterprise Linux

Issue

• Why does the broker print the following message "Could not accept socket: Too many open files (qpid/sys/posix/Socket.cpp:220)" in Red Hat Enterprise Linux

      From qpidd log's

     2010-11-03 15:50:44 error Could not accept socket: Too many open files (qpid/sys/posix/Socket.cpp:220)

     or

    jexception 0x0400 fcntl::clean_file() threw JERR_FCNTL_OPENWR: Unable to open file for write. (open() failed: errno=24 (Too many open files))

• How to estimate the maximum number of file handles required

• Does each durable queues consume file handle ?

• Other than durable Queue, is there any other objects that consume file handles ?