[SCore-users] Communication Performance with Score, with and without network trunking

[Viet]

Dear Users,

We have installed Score on a cluster of 2 nodes. We want to increase
communication speed with network trunking with a dual port NIC.
Howerver, we cannot get a good communication performance with Score.

Tested application: exchanging 16000 byte long messages between 2 nodes
(in fact, we performed the experiments with several message sizes and
show here only results of 16000 byte long, test result for other sizes
are in a similar pattern: single port no Score > dual port channel
bonding no Score > Score network trunking > Score single port)

Exchange bandwidth:
	without Score    + single port: 950 Mbps
			+ dual port, channel bonding (Linux, FC3): 610
Mbps
	with Score	+ single port: 415 Mbps
			+ dual port:  430 Mbps

Do I have any mistake in Score configuration?

Hardware platform:
+ Dell PowerEdge 1850 
+ 2 Dual-core Intel Xeon 2.8GHz processors
+ 4 GB Memory
+ Intel PRO 1000 PT Dual Gigabit Ethernet Adapter (PCI-Express x4)
+ Fedora-core 3 for x86-64
+ Score installed by source
+ Hostnames: ypc0515.jp and ypc0516.jp, 
+ ypc0515 as server and compute host.


Score configuration files are as follows:
1.scorehosts.db:
/* PM/Ethernet */
ethernet0		type=ethernet \
		-config:file=/opt/score/etc/pm-ethernet-0.conf
ethernet1		type=ethernet \
		-config:file=/opt/score/etc/pm-ethernet-1.conf
ethernet-x2	type=ethernet \
		-config:file=/opt/score/etc/pm-ethernet-1.conf \
		-trunk0:file=/opt/score/etc/pm-ethernet-0.conf
shmem0		type=shmem -node=0
shmem1		type=shmem -node=1
shmem2		type=shmem -node=2
shmem3		type=shmem -node=3

/*Macro to difine a host */
#define PCC	msgbserv=(ypc0515.jp:8764) \
		cpugen=XeonEMT speed=2800 smp=4 \
		network=ethernet-x2,shmem0,shmem1,shmem2,shmem3 \
		group=pcc
ypc0515.jp	PCC
ypc0516.jp	PCC
(for network trunking test, and network=ethernet0 for single port test)


2.pm-ethernet-0.conf:
unit 0
maxnsend 32
backoff 1000
checksum 0
# PE 	MAC address		base hostname		# comment
0	00:0E:0C:B3:BD:90	ypc0515.jp	# ip=10.0.5.150 on eth0
1	00:0E:0C:B4:18:CA	ypc0516.jp	# ip=10.0.5.160 on eth0

3.pm-ethernet-1.conf:
unit 1
maxnsend 32
backoff 1000
checksum 0
# PE 	MAC address		base hostname		# comment
0	00:0E:0C:B3:BD:91	ypc0515.jp	# on eth1
1	00:0E:0C:B4:18:CB	ypc0516.jp	# on eth1

Thank you very much for your help.

Ta Quoc Viet