From: jheard <jheard@...>
Date: 2002-06-01T20:27:48+09:00
Subject: net/ftp is cpu bound on fast internet connections

I was trying to run multiple ftp.putbinaryfile jobs and noticed that if 
I run more than say 2 threads on my PIII 933, My CPU usage hits 100% and 
my IO stays about the same, even though I am nowhere close to my 
theorectical limit.  Here's the original code.

1.upto(5) {|server_suffix|
   puts "starting send to DL360#{server_suffix}"
   threads[server_suffix] = Thread.new {
	ftp[server_suffix].putbinaryfile '100recs.tar.gz',
					 '100recs.tar.gz'

         telnet[server_suffix].cmd 'tar -xzf 100recs.tar.gz'
   }
}
threads[1..5].each {|thread| thread.join}

My connection should actually be able to handle about 20 of these 
threads at a time.  What I noticed was that of course ftp.rb's routines 
are block oriented and pass everything through yield to a block for 
processing.  I was wondering if it would be good for me or someone to 
add non block-oriented functions that perhaps even memory map and or 
buffer files where appropriate to save cpu time.