[Spread-users] packet loss? (win2000)

[Fernando Marotta]

Hi Yair,

I tried the out-of-the-box spflooder and had the same results:
I sent messages using the following command:

		spflooder -u sender -m 1000 -b 100 -wo

and received that using:

		spflooder -u recv -m 1000 -b 100 -ro

spread is in execution with this configuration file:

-------------------------------------------------------------
Spread_Segment  127.0.0.255:4803 {

	localhost		127.0.0.1
}

Spread_Segment  172.255.255.255:4803 {

	itwks2053		172.16.3.129
}




# Spread options
DebugFlags = { PRINT EXIT }

DangerousMonitor = false
----------------------------------------------------------------


(I had to insert my machine twice: having only the loopback interface
'localhost' won't work...)

Then, to complete the "message reception" I had to run the send 3 times (so
more or less the same packet loss). 
I also saw that if I change the spread process priority to "above normal" in
Win2000 (while all the spflooder have "normal" priority) all the messages
are received, but the packet rate is very little (<100 msg/sec).

Maybe I'm making something wrong, and/or you can give me some idea. (I
really hope so).

BTW, I also had another question: I read that spread may uses broadcast as
performance optimization; there is a way of disabling this behavior? (I
would like to try spread in an environment where other sw are running using
broadcast, and would prefer avoiding the broadcast storm effect).

Thanks.
Cheers

Fernando







> -----Original Message-----
> From: Yair Amir [mailto:yairamir at cnds.jhu.edu]
> Sent: domenica 21 luglio 2002 15.44
> To: spread-users-admin at lists.spread.org; Fernando Marotta
> Cc: spread-users at lists.spread.org
> Subject: Re[2]: [Spread-users] packet loss?
> 
> 
> Hi Fernando,
> 
> I run similar tests on my machine but I did not experience any
> message loss in any of the tests.
> 
> What I thought initially is that your client was disconnected with
> 1000 messages, so I wanted you to run with 10,000 and 100,000 messages
> to see if you receive any more messages. It seems that you do and that
> you are loosing some percentage of your messages. This is really odd.
> I never saw Spread configuration that behaves like that.
> 
> You should run the out-of-the-box spflooder. Maybe the problem is in
> your changes.
> 
> Having said that, I did experience a very slow Spread operation when
> running on Win2000 and one daemon in the system - as in your
> experiment. Spread did about 120 mess/sec only (compared with
> 10,000 at least I would expect). More on that in the next message.
> 
>        Cheers,
> 
>        :) Yair.
>        
> Fernando> I'm printing on the screen every 100 messages received.
> 
> Fernando> sending 10.000 msgs the receiver gets 7600-7800 of them
> Fernando> sendong 100.000 msgs the received are about 97.000
> 
> Fernando> what do you think the problem is?
> 
> Fernando> thanks for your help, I really appreciate it.
> 
> Fernando> cheers
> 
> Fernando> Fernando
> 
> 
> 
> 
> >> -----Original Message-----
> >> From: Yair Amir [mailto:yairamir at cnds.jhu.edu]
> >> Sent: giovedì 18 luglio 2002 18.25
> >> To: spread-users-admin at lists.spread.org; Fernando Marotta
> >> Cc: spread-users at lists.spread.org
> >> Subject: Re: [Spread-users] packet loss?
> >> 
> >> 
> >> I think I know what your problem is.
> >> Try sending 10,000 messages and tell us how many you receive.
> >> Also try 100,000 messages.
> >> 
> >>      Thanks,
> >> 
> >>      :) Yair.
> >>      
> >> Fernando> Hi everybody,
> >> 
> >> Fernando> I downloaded a couple of days ago spread, and found 
> >> it very interesting.
> >> Fernando> Just to test its performance I modified slightly 
> >> the "spflooder" program, to
> >> Fernando> show the time elapsed from the first to the last 
> >> message received (receiving
> >> Fernando> mode).
> >> 
> >> Fernando> I'm using spread under Win2K (3.16.2, binary distro).
> >> 
> >> Fernando> My "tests" are with one sender and one receiver 
> >> (and the spread exe) on the
> >> Fernando> same machine.
> >> 
> >> Fernando> I've experienced a high packet loss rate, 
> >> regardless of the delivery mode in
> >> Fernando> the SP_send call (I've used all, from UNRELIABLE 
> to SAFE).
> >> Fernando> But, for instance, when sending 1000 msgs of 100 
> >> bytes, no more than 700
> >> Fernando> msgs are received.
> >> 
> >> Fernando> Probably I'm making some mistakes....
> >> 
> >> Fernando> Any idea?
> >> 
> >> Fernando> Thanks in advance.
> >> Fernando> Cheers
> >> 
> >> Fernando> Fernando.
> >> 
> >> 
> >> Fernando> _______________________________________________
> >> Fernando> Spread-users mailing list
> >> Fernando> Spread-users at lists.spread.org
> >> Fernando> http://lists.spread.org/mailman/listinfo/spread-users
> >> 
> 
> Fernando> _______________________________________________
> Fernando> Spread-users mailing list
> Fernando> Spread-users at lists.spread.org
> Fernando> http://lists.spread.org/mailman/listinfo/spread-users
>