37 lines
1 KiB
Markdown
37 lines
1 KiB
Markdown
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---
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title: 'How to increase /dev/shm size on kubernetes'
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description: "the equivalent to docker's shm-size flag"
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date: '2024-10-02'
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tags:
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- kubernetes
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---
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## Introduction
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Today I had to find a way to increase the size of the shared memory filesystem offered to containers for a specific workload. `/dev/shm` is a Linux specific `tmpfs` filesystem that some applications use for inter process communications. The defaults size of this filesystem on kubernetes nodes is 64MiB.
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Docker has a `--shm-size 1g` flag to specify that. Though kubernetes does not offer a direct equivalent, we can replicate this with volumes.
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## Configuration in pod specification
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Here are the relevant sections of the spec we need to set:
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``` yaml
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spec:
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template:
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spec:
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container:
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volume_mount:
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mount_path = "/dev/shm"
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name = "dev-shm"
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read_only = false
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volume:
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empty_dir:
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medium = "Memory"
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size_limit = "1Gi"
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name = "dev-shm"
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```
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## Conclusion
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Well it works!
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