Nodes

Information on Installed Nodes

There are 3 "generations" of nodes installed on the cluster. The oldest nodes are AMD dual core, the medium-old nodes are Intel Core 2 quad cores, and the latest nodes are Intel Xeon quad cores and Intel Core i7 quad cores with HyperThreading. The specifications of each node are given in detail below.

All nodes use Debian Testing (Wheezy) as their operating system.

Intel Core i7 Nodes

Core i7s nodes are quad cores with HyperThreading. This means that they have 4 cores, but present 8 cores to the operating system. Therefore you will see these nodes having 8 CPUs when looking at them in Ganglia. Since they actually only have 4 cores, you will not get a linear increase in speed once the CPU is running more than 4 threads. However, since there still is a perceptible increase in speed, it is beneficial to use all 8 threads rather than just limiting yourself to 4.

We currently have 15 of these nodes in the cluster.

Node Name	Node CPU	RAM	Swap
node3	Core i7 860 @ 2.80 GHz	12 GB	90 GB
node4	Core i7 860 @ 2.80 GHz	12 GB	230 GB
node5	Core i7 860 @ 2.80 GHz	8 GB	230 GB
node6	Core i7 860 @ 2.80 GHz	8 GB	230 GB
node7	Core i7 860 @ 2.80 GHz	8 GB	90 GB
node8	Core i7 860 @ 2.80 GHz	4 GB	90 GB
node9	Core i7 2600 @ 3.40 GHz	16 GB	184 GB
node10	Core i7 860 @ 2.80 GHz	8 GB	230 GB
node11	Core i7 860 @ 2.80 GHz	8 GB	230 GB
node12	Core i7 860 @ 2.80 GHz	8 GB	230 GB
node13	Core i7 860 @ 2.80 GHz	8 GB	230 GB
node14	Core i7 860 @ 2.80 GHz	8 GB	230 GB
node15	Currently Unoperational	8 GB	10 GB
node21	Core i7 2600 @ 3.40 GHz	16 GB	184 GB
node31	Core i7 2600 @ 3.40 GHz	16 GB	184 GB

Intel Xeon Virtual Nodes

There are five virtual nodes running inside Windows workstations. Each of them has a quad core Intel Xeon of SandyBridge architecture, identical to the Core i7s, but without HyperThreading. This machines are connected to the rest of the cluster nodes by a virtual private network (VPN), which is ~1.5 order of magnitude slower than the Gigabit interconnect used by the no-virtual nodes. Therefore these machines should NOT be used for MPI jobs. Virtual nodes are best suited for sequential programs, OpenMP jobs, and code development.

Node Name	Node CPU	RAM	Swap
vnode1	Xeon E31220 @ 3.10 GHz	8 GB	50 GB
vnode2	Xeon E31220 @ 3.10 GHz	8 GB	50 GB
vnode3	Xeon E31220 @ 3.10 GHz	8 GB	50 GB
vnode4	Xeon E31220 @ 3.10 GHz	8 GB	50 GB
vnode5	Xeon E31220 @ 3.10 GHz	8 GB	50 GB

Intel Core 2 Quad Nodes

These are slightly older machines. They have 4 physical cores and no HyperThreading, so when you look at them in Ganglia you will see that they have 4 CPUs. They are still reasonably fast.

We currently have 8 of these nodes in the cluster. In addition, node18 has a similar architecture, but has 2 CPUs (8 cores total).

Node Name	Node CPU	RAM	Swap
node1	Currently Unoperational	8 GB	680 GB
node2	Core 2 Quad Q8200 @ 2.33 GHz	8 GB	90 GB
node18	2x 4-core Xeon L5420 @ 2.50 GHz	8 GB	80 GB
node25	Core 2 Quad Q8200 @ 2.33 GHz	8 GB	649 GB
node26	Core 2 Quad Q8200 @ 2.33 GHz	8 GB	649 GB
node27	Core 2 Quad Q8200 @ 2.33 GHz	8 GB	649 GB
node28	Core 2 Quad Q8200 @ 2.33 GHz	8 GB	10 GB
node29	Core 2 Quad Q8200 @ 2.33 GHz	8 GB	90 GB
node30	Core 2 Quad Q8200 @ 2.33 GHz	4 GB	649 GB

AMD Dual Core Nodes

These are the "ancient" machines. They have two physical cores, and also no HyperThreading. If speed isn't that important you should use these nodes. They're also good at adding some speed to your MPI MCNP runs when using the balance flag. Compiling and other disk I/O tasks are also suited well to these nodes, since all nodes have the same delay when writing to the file servers.

We currently have 7 of these nodes in the cluster.

Node Name	Node CPU	RAM	Swap
node16	Athlon 64 X2 5200+	8 GB	184 GB
node17	Athlon 64 X2 5200+	8 GB	184 GB
node19	Athlon 64 X2 5200+	8 GB	10 GB
node20	Athlon 64 X2 5200+	6 GB	184 GB
node22	Athlon 64 X2 5200+	8 GB	10 GB
node23	Athlon 64 X2 5200+	8 GB	10 GB
node24	Athlon 64 X2 5200+	8 GB	10 GB