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1. IL-0427 A GPU with uncorrectable ECC errors crashed tr1-13B training, and Slurm's next job went to the same node and crashed too

   BigScience2021

   Symptoms

   After many hours of training, one job of the tr1-13B Slurm job array crashed at iteration 43680 of 311541 during the backward pass. The next job in the array started by itself and crashed right away, before training began.

   Training job failureGPU unavailable

   Trigger

   One GPU on one node of the allocation developed a hardware problem that produced uncorrectable ECC errors.

   Root cause

   Hardware failure

   Component

   GPU hardware and memorySlurm job scheduler

   Contributing factor

   Automation amplificationMonitoring blind spot

   Detection

   Nobody was around to notice the first crash, and the Slurm scheduler started the next job in the array on its own, which crashed too.

   Remediation

   • Contacted the JZ administrators, who confirmed one of the nodes was faulty
   • Continued training with the next job, which was not placed on the faulty node

   Action items

   • Add %N to the Slurm output setting (#SBATCH --output=%x-%j-%N.out) so each node writes its own log file and the node with a corrupt GPU can be identified
   • Exclude a node known to be faulty from the allocation with sbatch --exclude

   Lessons

   Without a way to link an exception to the hostname of the node that raised it, the scheduler can keep placing the training on the faulty node and the training keeps crashing; per-node log files make the faulty node visible so it can be excluded.

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