forked from mirrors/gotosocial
acc333c40b
When GTS is running in a container runtime which has configured CPU or memory limits or under an init system that uses cgroups to impose CPU and memory limits the values the Go runtime sees for GOMAXPROCS and GOMEMLIMIT are still based on the host resources, not the cgroup. At least for the throttling middlewares which use GOMAXPROCS to configure their queue size, this can result in GTS running with values too big compared to the resources that will actuall be available to it. This introduces 2 dependencies which can pick up resource contraints from the current cgroup and tune the Go runtime accordingly. This should result in the different queues being appropriately sized and in general more predictable performance. These dependencies are a no-op on non-Linux systems or if running in a cgroup that doesn't set a limit on CPU or memory. The automatic tuning of GOMEMLIMIT can be disabled by either explicitly setting GOMEMLIMIT yourself or by setting AUTOMEMLIMIT=off. The automatic tuning of GOMAXPROCS can similarly be counteracted by setting GOMAXPROCS yourself.
54 lines
1.9 KiB
Markdown
54 lines
1.9 KiB
Markdown
# eBPF
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[](https://pkg.go.dev/github.com/cilium/ebpf)
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eBPF is a pure Go library that provides utilities for loading, compiling, and
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debugging eBPF programs. It has minimal external dependencies and is intended to
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be used in long running processes.
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* [asm](https://pkg.go.dev/github.com/cilium/ebpf/asm) contains a basic
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assembler
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* [link](https://pkg.go.dev/github.com/cilium/ebpf/link) allows attaching eBPF
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to various hooks
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* [perf](https://pkg.go.dev/github.com/cilium/ebpf/perf) allows reading from a
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`PERF_EVENT_ARRAY`
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* [cmd/bpf2go](https://pkg.go.dev/github.com/cilium/ebpf/cmd/bpf2go) allows
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embedding eBPF in Go
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The library is maintained by [Cloudflare](https://www.cloudflare.com) and
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[Cilium](https://www.cilium.io). Feel free to
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[join](https://cilium.herokuapp.com/) the
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[#libbpf-go](https://cilium.slack.com/messages/libbpf-go) channel on Slack.
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## Current status
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The package is production ready, but **the API is explicitly unstable right
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now**. Expect to update your code if you want to follow along.
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## Requirements
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* A version of Go that is [supported by
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upstream](https://golang.org/doc/devel/release.html#policy)
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* Linux 4.9, 4.19 or 5.4 (versions in-between should work, but are not tested)
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## Useful resources
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* [eBPF.io](https://ebpf.io) (recommended)
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* [Cilium eBPF documentation](https://docs.cilium.io/en/latest/bpf/#bpf-guide)
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(recommended)
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* [Linux documentation on
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BPF](https://www.kernel.org/doc/html/latest/networking/filter.html)
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* [eBPF features by Linux
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version](https://github.com/iovisor/bcc/blob/master/docs/kernel-versions.md)
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## Regenerating Testdata
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Run `make` in the root of this repository to rebuild testdata in all
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subpackages. This requires Docker, as it relies on a standardized build
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environment to keep the build output stable.
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The toolchain image build files are kept in [testdata/docker/](testdata/docker/).
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## License
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MIT
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