Algorithm

• shawnsmithdev/zermelo - A radix sorting library for Go.

Articles

• Debugging performance issues in Go programs by Dmitry Vyukov (2014)
• Go Wiki: Compiler And Runtime Optimizations
• High Performance Go workshop by Dave Cheney (2019)
• The official HOW-TO on app diagnostics

Assembly

• go/doc/asm - A Quick Guide to Go's Assembler.
• mmcloughlin/avo - Generate x86 Assembly with Go.
• CAFxX/atomics - All the missing AMD64 atomic instructions.

Benchmarks

• x/perf/cmd/benchstat - Benchstat computes statistical summaries and A/B comparisons of Go benchmarks.
• storozhukBM/benchart - Tool that takes benchstat -csv output as an input and plots results of your benchmark in a html file.
• quasilyte/go-benchrun - Convenience wrapper around "go test" + "benchstat".

Compiling

• jordanlewis/gcassert - Assert your Go code is inlined and bounds-check eliminated.

Compression

• klauspost/compress - Optimized Go Compression Packages.
• pierrec/lz4 - LZ4 compression and decompression in pure Go.

Concurrency

• bcicen/grmon - Command line monitoring for goroutines.
• jonhoo/drwmutex - Distributed RWMutex in Go.

GC

• CAFxX/gcnotifier - Know when GC runs from inside your golang code.

Hardware

• klauspost/cpuid - Provides information about the CPU running the current program.

Hash

• minio/md5-simd - Accelerate aggregated MD5 hashing performance up to 8x for AVX512 and 4x for AVX2.
• zeebo/xxh3 - XXH3 algorithm in Go.

IO

• smallnest/preallocate - File preallocation library.

Math

• bmkessler/fastdiv - Fast division, modulus and divisibility checks in Go for divisors known only at runtime.

Network

• valyala/fasthttp - Fast HTTP package for Go. Tuned for high performance. Zero memory allocations in hot paths. Up to 10x faster than net/http.
• gnet - high-performance, lightweight, non-blocking, event-driven networking framework written in pure Go.

Other

• templexxx/tsc - Get unix time (nanoseconds) in 8ns, 10x faster than stdlib.

Profiling

• pyroscope - A modern open source continuous profiling platform for debugging Go performance issues down to a single line of code.
• profefe - Continuous profiling data collecting.
• google/pprof - pprof is a tool for visualization and analysis of profiling data.
• felixge/fgprof - a sampling Go profiler that allows you to analyze On-CPU as well as Off-CPU (e.g. I/O) time together.
• parca - Parca is a continuous profiling project for applications and infrastructure, built with Go for Go.

Storage

• philpearl/stringbank - Storing strings without GC overhead.