I'm using Gitlab shared runner with Docker (current runner version: 10.0.2, docker storage driver: overlay2), running on AWS t2.small instance. I started experiencing issues with builds slowing down after some time (it's hard to say when exactly they become slow) - they take ~10x more time to finish than before. After killing the instance problem disappears for a while and after some time it slows down again.
Things I already checked:
- CPU usage on machine is around 20% the whole time
- RAM usage is around 1,5 G during the heaviest build
- IOPS on EBS are not exhausting all Burst Balance (e.g. right now burst balance is around 80%)
- Download speed
What else might be causing this ?
Just in case, jobs that are running on this runner are mostly yarn install and yarn build of a medium-sized front-end React application.