Slurm MultiNode

This repository facilitates job submission with multi-node and multi-GPU configurations in Slurm using Torchrun.

Overview

This repository provides scripts that are helpful when using multinode with PyTorch DDP module in Slurm. It consists of master.sh and original.sh, where master.sh submits original.sh for each node. The example involves using a total of 32 GPUs across 4 nodes, each with 8 GPUs. The scripts offer color coding for sanity checks and also include a memo feature.

Contents

• Checking Node Socket Information
• Multi-Node Slurm Job

Environment

• Slurm Version: 21.08.8-2
• Pytorch Version: Recommended 1.8 and above
• Ubuntu Version: 20.04.5 LTS

NCCL Setting

Handling "NCCL WARN Bootstrap: no socket interface found" Error

Ensure proper socket naming by following the instructions provided in the repository.

Setting the Appropriate Interface for Distributed Launch

If you intend to use distributed launch, set the "appropriate interface" for your environment. You can check your available interfaces using the following commands:

$ ifconfig
or
$ /sbin/ifconfig -a

The chosen Ethernet Interface name should have both inet6 and broadcast properties. This socket name will be used later, so carefully note your interface name.

Examples of Interface Information (ifconfig)

en***: flags=****<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
        inet <inet ip>  netmask 255.255.255.0  broadcast <broadcast add>
        inet6 f****::****:****:****:****  prefixlen 64  scopeid 0x20<link>
        ether **:36:**:**:**:**  txqueuelen 1000  (Ethernet)
        RX packets 16632361209  bytes 24172178960947 (24.1 TB)
        RX errors 0  dropped 43641438  overruns 0  frame 0
        TX packets 16585505941  bytes 24290665224417 (24.2 TB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

Choose the Ethernet Interface name with inet6 and broadcast properties for later use.

To set the NCCL_SOCKET_IFNAME, use the chosen Ethernet interface name.

For example:

export NCCL_SOCKET_IFNAME=en***

References

1. Nvidia Environment Variables Official Docs
2. Linux Commands about Net interface

Feel free to enhance the design for improved clarity and aesthetics.