# Hanging XMLRPC calls

**URL:** <https://www.ruby-forum.com/t/hanging-xmlrpc-calls/176072>\
**Category:** Ruby\
**Created:** [September 24, 2009, 10:27am UTC](https://www.ruby-forum.com/t/hanging-xmlrpc-calls/176072 "2009-09-24T10:27:56Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![rickthemick](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/r/6bbea6/32.png) [@rickthemick](https://www.ruby-forum.com/u/rickthemick)\
**Post date:** [September 24, 2009, 10:27am UTC](https://www.ruby-forum.com/t/hanging-xmlrpc-calls/176072/1 "2009-09-24T10:27:56Z")

</div>

Hi!

I have a problem with hanging XMLRPC calls. It appears when I call  
XMLRPC::Client.new too freqently. For my own sake, I have a work around  
for this (I save the server reference in an instance variable, for  
example).

But this might be of interest for other people. And my idea was to show  
this for you Ruby people with more insight into this area.

As you can see below sometimes the call hangs for 30 seconds. Note that  
it appears even when sleeping 5 seconds between the instantiations.

This is a really simple piece of code!

Best Regards  
///Rickard

# Here is the code:

#!/app/ruby/1.8.x/bin/ruby

require “xmlrpc/client”

# Server code (from

[Using XML-RPC with Ruby](http://tldp.org/HOWTO/XML-RPC-HOWTO/xmlrpc-howto-ruby.html)):  
##!/app/ruby/1.8.x/bin/ruby  
#require “xmlrpc/server”  
#s = XMLRPC::Server.new(4001)

# 

#class MyHandler

# def sumAndDifference(a, b)

# { “sum” =\> a + b, “difference” =\> a - b }

# end

#end

# 

#s.add\_handler(“sample”, MyHandler.new)  
#s.serve  
##end of server code

def call\_server(sleeptime)  
puts “\*\*\*\* Trying with sleeptime #{sleeptime} sec \*\*\*\*”

# Create server reference outside of loop (this works fine)

#Server = XMLRPC::Client.new(“127.0.0.1”, “/”, 4001)

for i in 1…7

```
# Create server reference inside of loop (this creates the problem,

```

when called frequently)  
server = XMLRPC::Client.new(“127.0.0.1”, “/”, 4001)

```
start = Time.now.tv_sec
result = server.call("sample.sumAndDifference", 5, 3)
total = Time.now.tv_sec - start

# print result and number of seconds spent during the remote call
puts "Result: #{result.inspect}. Time: #{total} sec"

# just to show we dont need to stress "that much"
# it seems that it doensnt hang when sleep >= 10 sec (on my linux

```

machine)  
Kernel.sleep(sleeptime)

end  
end

[0,5,7,10].each do |sleeptime|  
call\_server(sleeptime)  
end

# Here is the output:

; ./client.rb  
\*\*\*\* Trying with sleeptime 0 sec \*\*\*\*  
Result: {“sum”=\>8, “difference”=\>2}. Time: 0 sec  
Result: {“sum”=\>8, “difference”=\>2}. Time: 0 sec  
Result: {“sum”=\>8, “difference”=\>2}. Time: 0 sec  
Result: {“sum”=\>8, “difference”=\>2}. Time: 0 sec  
Result: {“sum”=\>8, “difference”=\>2}. Time: 30 sec  
Result: {“sum”=\>8, “difference”=\>2}. Time: 0 sec  
Result: {“sum”=\>8, “difference”=\>2}. Time: 0 sec  
\*\*\*\* Trying with sleeptime 5 sec \*\*\*\*  
Result: {“sum”=\>8, “difference”=\>2}. Time: 0 sec  
Result: {“sum”=\>8, “difference”=\>2}. Time: 20 sec  
Result: {“sum”=\>8, “difference”=\>2}. Time: 0 sec  
Result: {“sum”=\>8, “difference”=\>2}. Time: 0 sec  
Result: {“sum”=\>8, “difference”=\>2}. Time: 0 sec  
Result: {“sum”=\>8, “difference”=\>2}. Time: 10 sec  
Result: {“sum”=\>8, “difference”=\>2}. Time: 0 sec  
\*\*\*\* Trying with sleeptime 7 sec \*\*\*\*  
Result: {“sum”=\>8, “difference”=\>2}. Time: 0 sec  
Result: {“sum”=\>8, “difference”=\>2}. Time: 0 sec  
Result: {“sum”=\>8, “difference”=\>2}. Time: 4 sec  
Result: {“sum”=\>8, “difference”=\>2}. Time: 0 sec  
Result: {“sum”=\>8, “difference”=\>2}. Time: 0 sec  
Result: {“sum”=\>8, “difference”=\>2}. Time: 0 sec  
Result: {“sum”=\>8, “difference”=\>2}. Time: 2 sec  
\*\*\*\* Trying with sleeptime 10 sec \*\*\*\*  
Result: {“sum”=\>8, “difference”=\>2}. Time: 0 sec  
Result: {“sum”=\>8, “difference”=\>2}. Time: 0 sec  
Result: {“sum”=\>8, “difference”=\>2}. Time: 0 sec  
Result: {“sum”=\>8, “difference”=\>2}. Time: 0 sec  
Result: {“sum”=\>8, “difference”=\>2}. Time: 0 sec  
Result: {“sum”=\>8, “difference”=\>2}. Time: 0 sec  
Result: {“sum”=\>8, “difference”=\>2}. Time: 0 sec

---

<div class="post-metadata">

**Author:** ![rickthemick](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/r/6bbea6/32.png) [@rickthemick](https://www.ruby-forum.com/u/rickthemick)\
**Post date:** [September 29, 2009, 8:53am UTC](https://www.ruby-forum.com/t/hanging-xmlrpc-calls/176072/2 "2009-09-29T08:53:22Z")

</div>

I have been told that this problem occurs since the garbage collector  
doesnt close the new sockets in the same rate as I create new ones.

Then, the first idea was to use a “close” method, but of what I can see  
it doesnt exist. So instead I tried to force the garbage collector to  
run, which actually works. But, is it a good idea to do this? Some  
other, better way to acheive this?

loop

client = Client.new  
client.call(…)

#client.close #doesnt work, “undefined method”

ObjectSpace.garbage\_collect #works fine

end

Regards  
/Rickard