Re: [Condor-users] condor performance on quad core vs dual core machines

["Kewley, J \(John\)" <john.kewley@xxxxxxxxxx>]

When you say:

2 Dual Core
CPU: Xeon 3GHz
RAM:  4GB

and

 

2 Quad Core
CPU: Xeon 3GHz
RAM:  4GB

Is the RAM you quote per-core or per-node or per-machine?

 

[Using my terminology:

 Cluster 1: each machine = 2 nodes = 2x2=4 cores

 Cluster 2: each machine = 2 nodes = 2x4=8 cores]

 

If it is per-core and jobs in the DAG are independent (not for instance MPI)

I'd guess you should get fairly similar figures if the jobs are compute

intensive. If they are IO-bound then 8 cores trying to do IO at the same time

could well take longer than 4 cores on each of two machines.

 

If it is per-node or per-machine, then if the jobs will have less RAM

per core on Cluster 2 (1GB or 0.5GB respectively) than on Cluster 1

(2GB or 1GB resp.) and this would likely be detrimental to performance.

 

JK

 

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From: condor-users-bounces@xxxxxxxxxxx [mailto:condor-users-bounces@xxxxxxxxxxx] On Behalf Of Maryam Khademi
Sent: Friday, December 05, 2008 3:32 AM
To: Condor-Users Mail List
Subject: [Condor-users] condor performance on quad core vs dual core machines

Hi,

I have a performance question. Currently, I am using two clusters to execute my DAGs on.

On the first cluster, each machine has a two dual core CPU, whilst a machine on the second cluster has a two quad core CPU.

I run the same DAG on each cluster while there are equal number of cores available on both. For example, 8 unclaimed cores (2 machines) on cluster #1 and 8 unclaimed cores (1 machine) on cluster #2.

Interestingly, almost always I got better result on the dual core machines cluster!

These are the rest of particulars:

Cluster #1:

2 Dual Core
CPU: Xeon 3GHz
RAM:  4GB
OS: Linux
Condor Version: 6.8.0
Platform: X86_64-LINUX_RHEL3
Globus version: 4.0.4

Cluster #2:

2 Quad Core
CPU: Xeon 3GHz
RAM:  4GB
OS: Red Hat Enterprise Linux Server release 5.1
OCS Version: Kusu 5 (build 1619)
Condor-version: 7.0.4
condor-platform: X86_64-LINUX_RHEL5
Globus version: 4.2.1

Thanks,
Maryam

P.S. All the above said are with the assumption that condor uses multi cores not single core in case of their availability.