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Overheads

 

Table 2 summarizes the time needed to complete a successful request or reply call. The difference between these two operations is that am_request_N() calls am_poll() after the message is sent while am_reply_N() does not. The time needed to complete am_poll() varies with the number and kind of messages received. The overhead of polling an empty network is 1.3 tex2html_wrap_inline866 s. The additional overhead per one received message is about 1.8 tex2html_wrap_inline868 s.

   table228
Table 2: Cost of calling am_request_N() and am_reply_N() functions. (The column for am_request_N() assumes that no messages are received as part of the am_poll which is performed inside am_request.)



Chris Hawblitzel
Thu Sep 19 12:22:33 EDT 1996