# Compute Nodes

## Nodes Configuration

Anselm is cluster of x86-64 Intel based nodes built on Bull Extreme Computing bullx technology. The cluster contains four types of compute nodes.

### Compute Nodes Without Accelerator

-   180 nodes
-   2880 cores in total
-   two Intel Sandy Bridge E5-2665, 8-core, 2.4GHz processors per node
-   64 GB of physical memory per node
-   one 500GB SATA 2,5” 7,2 krpm HDD per node
-   bullx B510 blade servers
-   cn[1-180]

### Compute Nodes With GPU Accelerator

-   23 nodes
-   368 cores in total
-   two Intel Sandy Bridge E5-2470, 8-core, 2.3GHz processors per node
-   96 GB of physical memory per node
-   one 500GB SATA 2,5” 7,2 krpm HDD per node
-   GPU accelerator 1x NVIDIA Tesla Kepler K20 per node
-   bullx B515 blade servers
-   cn[181-203]

### Compute Nodes With MIC Accelerator

-   4 nodes
-   64 cores in total
-   two Intel Sandy Bridge E5-2470, 8-core, 2.3GHz processors per node
-   96 GB of physical memory per node
-   one 500GB SATA 2,5” 7,2 krpm HDD per node
-   MIC accelerator 1x Intel Phi 5110P per node
-   bullx B515 blade servers
-   cn[204-207]

### Fat Compute Nodes

-   2 nodes
-   32 cores in total
-   2 Intel Sandy Bridge E5-2665, 8-core, 2.4GHz processors per node
-   512 GB of physical memory per node
-   two 300GB SAS 3,5”15krpm HDD (RAID1) per node
-   two 100GB SLC SSD per node
-   bullx R423-E3 servers
-   cn[208-209]

![](../img/bullxB510.png)
**Figure Anselm bullx B510 servers**

### Compute Nodes Summary

| Node type                  | Count | Range       | Memory | Cores       | [Access](resources-allocation-policy/) |
| -------------------------- | ----- | ----------- | ------ | ----------- | -------------------------------------- |
| Nodes without accelerator  | 180   | cn[1-180]   | 64GB   | 16 @ 2.4Ghz | qexp, qprod, qlong, qfree              |
| Nodes with GPU accelerator | 23    | cn[181-203] | 96GB   | 16 @ 2.3Ghz | qgpu, qprod                            |
| Nodes with MIC accelerator | 4     | cn[204-207] | 96GB   | 16 @ 2.3GHz | qmic, qprod                            |
| Fat compute nodes          | 2     | cn[208-209] | 512GB  | 16 @ 2.4GHz | qfat, qprod                            |

## Processor Architecture

Anselm is equipped with Intel Sandy Bridge processors Intel Xeon E5-2665 (nodes without accelerator and fat nodes) and Intel Xeon E5-2470 (nodes with accelerator). Processors support Advanced Vector Extensions (AVX) 256-bit instruction set.

### Intel Sandy Bridge E5-2665 Processor

-   eight-core
-   speed: 2.4 GHz, up to 3.1 GHz using Turbo Boost Technology
-   peak performance:  19.2 GFLOP/s per core
-   caches:
    -   L2: 256 KB per core
    -   L3: 20 MB per processor
-   memory bandwidth at the level of the processor: 51.2 GB/s

### Intel Sandy Bridge E5-2470 Processor

-   eight-core
-   speed: 2.3 GHz, up to 3.1 GHz using Turbo Boost Technology
-   peak performance:  18.4 GFLOP/s per core
-   caches:
    -   L2: 256 KB per core
    -   L3: 20 MB per processor
-   memory bandwidth at the level of the processor: 38.4 GB/s

Nodes equipped with Intel Xeon E5-2665 CPU have set PBS resource attribute cpu_freq = 24, nodes equipped with Intel Xeon E5-2470 CPU have set PBS resource attribute cpu_freq = 23.

```bash
$ qsub -A OPEN-0-0 -q qprod -l select=4:ncpus=16:cpu_freq=24 -I
```

In this example, we allocate 4 nodes, 16 cores at 2.4GHhz per node.

Intel Turbo Boost Technology is used by default,  you can disable it for all nodes of job by using resource attribute cpu_turbo_boost.

```bash
    $ qsub -A OPEN-0-0 -q qprod -l select=4:ncpus=16 -l cpu_turbo_boost=0 -I
```

## Memory Architecture

### Compute Node Without Accelerator

-   2 sockets
-   Memory Controllers are integrated into processors.
    -   8 DDR3 DIMMs per node
    -   4 DDR3 DIMMs per CPU
    -   1 DDR3 DIMMs per channel
    -   Data rate support: up to 1600MT/s
-   Populated memory: 8 x 8 GB DDR3 DIMM 1600 MHz

### Compute Node With GPU or MIC Accelerator

-   2 sockets
-   Memory Controllers are integrated into processors.
    -   6 DDR3 DIMMs per node
    -   3 DDR3 DIMMs per CPU
    -   1 DDR3 DIMMs per channel
    -   Data rate support: up to 1600MT/s
-   Populated memory: 6 x 16 GB DDR3 DIMM 1600 MHz

### Fat Compute Node

-   2 sockets
-   Memory Controllers are integrated into processors.
    -   16 DDR3 DIMMs per node
    -   8 DDR3 DIMMs per CPU
    -   2 DDR3 DIMMs per channel
    -   Data rate support: up to 1600MT/s
-   Populated memory: 16 x 32 GB DDR3 DIMM 1600 MHz