# Quieting DRb messages in fork() code

**URL:** <https://www.ruby-forum.com/t/quieting-drb-messages-in-fork-code/160677>\
**Category:** Ruby\
**Created:** [February 18, 2009, 6:39pm UTC](https://www.ruby-forum.com/t/quieting-drb-messages-in-fork-code/160677 "2009-02-18T18:39:40Z")\
**Posts on this page:** 5\
**Page:** 1

<div class="post-metadata">

**Author:** ![captaffy](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/c/f04885/32.png) [@captaffy](https://www.ruby-forum.com/u/captaffy)\
**Post date:** [February 18, 2009, 6:39pm UTC](https://www.ruby-forum.com/t/quieting-drb-messages-in-fork-code/160677/1 "2009-02-18T18:39:40Z")

</div>

Hi,

I’ve got some code which seems to work well, but the warning messages  
are driving me insane! I can’t use this code if it’s always going to  
spew warnings like these on a CentOS 5.2 system with ruby 1.8.5  
(2006-08-25) [i386-linux] as the environment. I’m also using  
slave-1.2.1 from [http://www.codeforpeople.com](http://www.codeforpeople.com)  
as well.

$ ./readdir-slave-only.rb --kids 4 tmp  
Starting Slave Counter  
Exception `DRb::DRbBadScheme' at /usr/lib/ruby/1.8/drb/drb.rb:814 - drbunix:///tmp/slave_counter_537520870_11835_11836_0_0.697410256497375 Exception `DRb::DRbBadScheme’ at /usr/lib/ruby/1.8/drb/drb.rb:814 -  
drbunix:///tmp/slave\_counter\_537520870\_11835\_11836\_0\_0.697410256497375  
Exception `DRb::DRbBadScheme' at /usr/lib/ruby/1.8/drb/drb.rb:814 - drbunix:///tmp/slave_counter_537520870_11835_11836_0_0.697410256497375 Exception `DRb::DRbBadScheme’ at /usr/lib/ruby/1.8/drb/drb.rb:814 -  
drbunix:///tmp/slave\_counter\_537520870\_11835\_11836\_0\_0.697410256497375  
Exception `DRb::DRbBadScheme’ at /usr/lib/ruby/1.8/drb/drb.rb:814 -  
drbunix:///tmp/slave\_counter\_537520870\_11835\_11836\_0\_0.697410256497375  
counter.count=0  
counter.max=4

@count incremented to 1  
Threaded!  
Exception `DRb::DRbBadScheme' at /usr/lib/ruby/1.8/drb/drb.rb:814 - drbunix:///tmp/slave_proc_537509010_11835_11839_0_0.449993964192234 Exception `DRb::DRbBadScheme’ at /usr/lib/ruby/1.8/drb/drb.rb:814 -  
drbunix:///tmp/slave\_proc\_537509010\_11835\_11839\_0\_0.449993964192234  
Exception `DRb::DRbBadScheme’ at /usr/lib/ruby/1.8/drb/drb.rb:814 -  
drbunix:///tmp/slave\_proc\_537509010\_11835\_11839\_0\_0.449993964192234  
#kids = 1  
Reaped a kid…  
@count incremented to 2

I’ve tried to capture these exceptions using ‘begin … rescue … end’  
blocks, but I’m obviously not doing something right. What’s frustrating  
is that when I pull the code out to just use ‘sleep’ calls, it seems to  
work just fine, without all the warnings.

I know my code is quite long, but even so it’s not complete since I need  
to insert my results into a DB at some point as well, so just getting  
the basics working will be a big help!

Here’s my code:

#!/usr/bin/ruby

require ‘getoptlong’  
#require ‘thread’  
require ‘slave’

$VERSION = “v1.1”;  
$max\_slaves = 1  
$count = 50

MYURI = “drbunix:/tmp/stoffj-test\_” + Process.pid.to\_s

opts = GetoptLong.new(  
[“–help”, “-h”, GetoptLong::NO\_ARGUMENT],  
[“–kids”, “-k”, GetoptLong::REQUIRED\_ARGUMENT]  
)

#---------------------------------------------------------------------  
class Counter  
def initialize(max)  
@slaves = []  
@max = max  
@count = 0  
@count\_mutex = Mutex.new  
end

def count  
@count  
end

def max  
@max  
end

# Increment the count of slaves, returning 1 if incremented, 0 if not.

def increment  
ok = nil  
@count\_mutex.synchronize do  
if (@count \< @max) then  
@count += 1  
puts “@count incremented to #{@count}”  
ok = 1  
end  
end  
ok  
end

# Decrement the count of slaves

def decrement  
@count\_mutex.synchronize do  
if (@count \> 1) then  
@count -= 1  
puts “@count decremented to #{@count}”  
end  
end  
@count  
end  
end

#---------------------------------------------------------------------  
class ReadDir  
def initialize(server)  
@server = server  
end

def readdir(dir)

```
#puts "readdir(#{dir})"
#sleep 1

size_file = {}
size_dir = {}
size_total = 0

kids = []

# Traverse the directory and collect the size of all files and
# directories

begin
  Dir.foreach(dir) do |f|
    #print " #{f},"
    if(f != "." && f != "..") then
      f_full = addpath(dir, f)
      stat = File.lstat(f_full)

      if(!stat.symlink?) then

        if(stat.file?) then
          #puts " File: #{f}"
          size = File.size(f_full)
          size_file[f] = size
          size_total += size
        end

        if(stat.directory?) then
          #puts "DIR= #{f}"
          if (@server.max < 2) then
            #puts " no threads."
            size = readdir(f_full)
            if (size > 0) then
              size_dir[f] = size
              size_total += size
            end
          else
            ok = @server.increment
            if (ok)
              puts " Threaded!"
              kids << Slave.object(:async => true, :threadsage =>

```

true) {  
size = readdir(f\_full)  
@server.decrement  
#puts “size = #{size}”  
# return the size from the slave properly  
size  
}  
puts “#kids = #{kids.length}”  
else  
size = readdir(f\_full)  
if(size \> 0) then  
size\_dir[f] = size  
size\_total += size  
end  
end  
end  
end  
end  
end  
end  
end

```
kids.each { |kid|
  puts "Reaped a kid..."
  size_total += kid.value
  @server.decrement
}

#Puts "Dir: #{dir} = #{size_total}"
return size_total

```

end

end

#---------------------------------------------------------------------

# Read a directory and add to the database; this function is recursive

# for sub-directories

#---------------------------------------------------------------------  
def usage  
puts  
puts “usage: readdir-drb [–kids NUM] ”  
puts " defaults to #{$max\_kids} children"  
puts  
puts " version: #{$version}"  
puts  
end

#---------------------------------------------------------------------  
def addpath(a, b)  
return a + b if(a =~ //$/)  
return a + “/” + b  
end

#---------------------------------------------------------------------

# Main

#---------------------------------------------------------------------  
$DEBUG = true

opts.each do |opt,arg|  
case opt  
when “–kids”  
$max\_slaves = arg.to\_i  
else  
usage  
exit  
end  
end

if ARGV.length != 1  
puts “Missing dir argument (try --help)”  
exit 0  
end

dir = ARGV.shift

# Start the Slave for Counting…

puts “Starting Slave Counter”  
slave = Slave.new :object =\> Counter.new($max\_slaves), :async =\> true

counter = slave.object  
puts “counter.count=#{counter.count}”  
puts “counter.max=#{counter.max}”  
puts

# Fire up a new Kid Class readdir.

kid = ReadDir.new(counter)

# Now let’s try to do a recursive readdir() algorith with threads.

size = kid.readdir(dir)

sizekb = size / 1024;  
sizemb = sizekb / 1024;  
sizegb = sizemb / 1024;

puts “”  
printf “Total size: %d Bytes\n”, size  
printf “Total size: %.2f Kb\n”, sizekb  
printf “Total size: %.2f Mb\n”, sizemb  
if (sizegb \> 1.5)  
printf “Total size: %.2f Gb\n”, sizegb  
end

---

<div class="post-metadata">

**Author:** ![captaffy](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/c/f04885/32.png) [@captaffy](https://www.ruby-forum.com/u/captaffy)\
**Post date:** [February 19, 2009, 5:17am UTC](https://www.ruby-forum.com/t/quieting-drb-messages-in-fork-code/160677/2 "2009-02-19T05:17:39Z")

</div>

John Stoffel wrote:

> Hi,
> 
> I’ve got some code which seems to work well, but the warning messages  
> are driving me insane! I can’t use this code if it’s always going to  
> spew warnings like these on a CentOS 5.2 system with ruby 1.8.5  
> (2006-08-25) [i386-linux] as the environment. I’m also using  
> slave-1.2.1 from [http://www.codeforpeople.com](http://www.codeforpeople.com)  
> as well.
> 
> $ ./readdir-slave-only.rb --kids 4 tmp  
> Starting Slave Counter  
> Exception `DRb::DRbBadScheme' at /usr/lib/ruby/1.8/drb/drb.rb:814 - drbunix:///tmp/slave_counter_537520870_11835_11836_0_0.697410256497375 Exception `DRb::DRbBadScheme’ at /usr/lib/ruby/1.8/drb/drb.rb:814 -  
> drbunix:///tmp/slave\_counter\_537520870\_11835\_11836\_0\_0.697410256497375

The exception is “normal” insofar as being expected behavior from DRb.  
It tries each loaded protocol until it finds a match, rescuing the  
non-matches.

You are seeing these messages because you have $DEBUG=true. If you are  
determined to avoid them in the presence of $DEBUG then you could put a  
preferred protocol at the beginning of the search list.

module DRb::DRbProtocol  
module\_function  
def prefer\_protocol(proto)  
@protocol.delete(proto)  
@protocol.unshift(proto)  
end  
end

DRb::DRbProtocol.prefer\_protocol(DRb::DRbUNIXSocket)

---

<div class="post-metadata">

**Author:** ![captaffy](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/c/f04885/32.png) [@captaffy](https://www.ruby-forum.com/u/captaffy)\
**Post date:** [February 19, 2009, 3:33pm UTC](https://www.ruby-forum.com/t/quieting-drb-messages-in-fork-code/160677/3 "2009-02-19T15:33:40Z")

</div>

James M. Lawrence wrote:

> John Stoffel wrote:
> 
> > Hi,
> > 
> > I’ve got some code which seems to work well, but the warning messages  
> > are driving me insane! I can’t use this code if it’s always going to  
> > spew warnings like these on a CentOS 5.2 system with ruby 1.8.5  
> > (2006-08-25) [i386-linux] as the environment. I’m also using  
> > slave-1.2.1 from [http://www.codeforpeople.com](http://www.codeforpeople.com)  
> > as well.
> > 
> > $ ./readdir-slave-only.rb --kids 4 tmp  
> > Starting Slave Counter  
> > Exception `DRb::DRbBadScheme' at /usr/lib/ruby/1.8/drb/drb.rb:814 - drbunix:///tmp/slave_counter_537520870_11835_11836_0_0.697410256497375 Exception `DRb::DRbBadScheme’ at /usr/lib/ruby/1.8/drb/drb.rb:814 -  
> > drbunix:///tmp/slave\_counter\_537520870\_11835\_11836\_0\_0.697410256497375
> 
> The exception is “normal” insofar as being expected behavior from DRb.  
> It tries each loaded protocol until it finds a match, rescuing the  
> non-matches.
> 
> You are seeing these messages because you have $DEBUG=true. If you are  
> determined to avoid them in the presence of $DEBUG then you could put a  
> preferred protocol at the beginning of the search list.
> 
> module DRb::DRbProtocol  
> module\_function  
> def prefer\_protocol(proto)  
> @protocol.delete(proto)  
> @protocol.unshift(proto)  
> end  
> end
> 
> DRb::DRbProtocol.prefer\_protocol(DRb::DRbUNIXSocket)

Duh, I feel like a fool now. I had forgotten about the $DEBUG setting  
(my mistake for burying it down low…) and now that I’ve turned it off,  
it’s much better! Now I can address my remaining issues with the code  
and final cleanup.

I would have hoped that DRb would have a DRb::DEBUG value instead, or at  
least something in the documentation which talks about this more since I  
was going nuts trying to figure out why it was so darn noisy.

This is a huge hug help, thanks!

John

---

<div class="post-metadata">

**Author:** ![captaffy](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/c/f04885/32.png) [@captaffy](https://www.ruby-forum.com/u/captaffy)\
**Post date:** [February 19, 2009, 5:34pm UTC](https://www.ruby-forum.com/t/quieting-drb-messages-in-fork-code/160677/4 "2009-02-19T17:34:04Z")

</div>

John Stoffel wrote:

> This is a huge hug help, thanks!

Sometimes we all need hug help 🙂

---

<div class="post-metadata">

**Author:** ![captaffy](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/c/f04885/32.png) [@captaffy](https://www.ruby-forum.com/u/captaffy)\
**Post date:** [February 19, 2009, 9:33pm UTC](https://www.ruby-forum.com/t/quieting-drb-messages-in-fork-code/160677/5 "2009-02-19T21:33:20Z")

</div>

Joel VanderWerf wrote:

> John Stoffel wrote:
> 
> > This is a huge hug help, thanks!
> 
> Sometimes we all need hug help 🙂

_laugh_ That’s very true. Now I’m actually getting useful work out of  
my script, though I’ve got a logic bug somewhere which is causing  
problems.

More questions as I figure out what I’m doing wrong.

John