[Spread-users] Performance evalution, bursty application traffic : are my results normal ?

[Pierre GARCIA]

Hi Spread Group,

I'm a new Spread User. I plan to use spread to safely multicast messages 
(from 1Ko to 100Ko) on 20
machines.

Description of the environment

Spread Version : 3.17.3
Switch                : Fast Ethernet
Nodes                 : - 2 x 900MHz Itanim2 cpu
                              - 3 Gbytes memory
                              - 2 x 36 Gbytes Hard Disks
                              - OS : Red Hat Enterprise Linux AS release 
3 (Taroon Update 5)


I have a bursty pattern to generate traffic. Thus, I tuned WATER_MARK 
and MAX_SESSION_MESSAGES to increase performances.

I have one daemon/client per node and my spread.conf looks like this :

spread.conf
--------------------------------
Spread_Segment xx.88.97.255:4803 {
    machine1 xx.88.97.61
}
Spread_Segment xx.88.97.255:4804 {
    machine2 xx.88.97.62
}
Spread_Segment xx.88.97.255:4805 {
    machine3 xx.88.97.63
}
Spread_Segment xx.88.97.255:4806 {
    machine4 xx.88.97.64
}
Spread_Segment xx.88.97.255:4807 {
    machine5 xx.88.97.65
}
Spread_Segment xx.88.97.255:4808 {
    machine6 xx.88.97.66
}
Spread_Segment xx.88.97.255:4809 {
    machine7 xx.88.97.67
}
Spread_Segment xx.88.97.255:4810 {
    machine8 xx.88.97.68
}
Spread_Segment xx.88.97.255:4811 {
    machine9 xx.88.97.69
}
Spread_Segment xx.88.97.255:4812 {
    machine10 xx.88.97.70
}
Spread_Segment xx.88.97.255:4813 {
    machine11 xx.88.97.71
}
Spread_Segment xx.88.97.255:4814 {
    machine12 xx.88.97.72
}
Spread_Segment xx.88.97.255:4815 {
    machine13 xx.88.97.73
}
Spread_Segment xx.88.97.255:4816 {
    machine14 xx.88.97.74
}
Spread_Segment xx.88.97.255:4817 {
    machine15 xx.88.97.75
}
Spread_Segment xx.88.97.255:4818 {
    machine16 xx.88.97.76
}
Spread_Segment xx.88.97.255:4819 {
    machine17 xx.88.97.77
}
Spread_Segment xx.88.97.255:4820 {
    machine18 xx.88.97.78
}
Spread_Segment xx.88.97.255:4821 {
    machine19 xx.88.97.79
}
Spread_Segment xx.88.97.255:4822 {
    machine20 xx.88.97.80
}

--------------------------

I have tried several other configurations (one segment per example), but 
performances were worst.

My experience is minimal : each client sends ~20Mo of data. This amount 
of data is divided in several messages (from 20000 messages of  1Ko to 
200 messages of  100Ko).

My RESULTS (Message size 10 Ko):

Nodes     Average Throughput (Mb/s)
2             83.93
3             45.02
4             30.33
5             22.85
6             18.3
7             15.29
10           10.22
15           6.57
20           4.85

For other sizes of message, the decrease is the same.

My questions are :

  1) Is it normal ? Did I make something wrong ?
 
  2) Is there other parameters in spread that can help me to increase 
performances ?

If anyone can answer, you're welcome,

Pierre
-------------- next part --------------
A non-text attachment was scrubbed...
Name: pierre2101.vcf
Type: text/x-vcard
Size: 352 bytes
Desc: not available
Url : http://lists.spread.org/pipermail/spread-users/attachments/20061018/ee157b7e/attachment.vcf