Jay Brown
477518e5eb
API instrumentation - metrics and logging * api instrumentation prometheus metrics and logging for all routes * Merge branch 'main' of bitbucket.org:aarete/query-orchestration into feature/prometheus * add log_level and sync the config initialize * docs * cleanup * add to compose:up:test * docs for prometheus testing * custom metrics * cleanup * merge main * add tests * cleanup docs * cleanup * lint * fix unit tests (attempt) * fix tests * resolvesetlogger * expose 8080 * compose changes * bugfixesformichael * don't build _test * merge in main * job_sync_runner
59 lines
2.0 KiB
Go
59 lines
2.0 KiB
Go
//go:build !appengine
|
|
// +build !appengine
|
|
|
|
// This file encapsulates usage of unsafe.
|
|
// xxhash_safe.go contains the safe implementations.
|
|
|
|
package xxhash
|
|
|
|
import (
|
|
"unsafe"
|
|
)
|
|
|
|
// In the future it's possible that compiler optimizations will make these
|
|
// XxxString functions unnecessary by realizing that calls such as
|
|
// Sum64([]byte(s)) don't need to copy s. See https://go.dev/issue/2205.
|
|
// If that happens, even if we keep these functions they can be replaced with
|
|
// the trivial safe code.
|
|
|
|
// NOTE: The usual way of doing an unsafe string-to-[]byte conversion is:
|
|
//
|
|
// var b []byte
|
|
// bh := (*reflect.SliceHeader)(unsafe.Pointer(&b))
|
|
// bh.Data = (*reflect.StringHeader)(unsafe.Pointer(&s)).Data
|
|
// bh.Len = len(s)
|
|
// bh.Cap = len(s)
|
|
//
|
|
// Unfortunately, as of Go 1.15.3 the inliner's cost model assigns a high enough
|
|
// weight to this sequence of expressions that any function that uses it will
|
|
// not be inlined. Instead, the functions below use a different unsafe
|
|
// conversion designed to minimize the inliner weight and allow both to be
|
|
// inlined. There is also a test (TestInlining) which verifies that these are
|
|
// inlined.
|
|
//
|
|
// See https://github.com/golang/go/issues/42739 for discussion.
|
|
|
|
// Sum64String computes the 64-bit xxHash digest of s with a zero seed.
|
|
// It may be faster than Sum64([]byte(s)) by avoiding a copy.
|
|
func Sum64String(s string) uint64 {
|
|
b := *(*[]byte)(unsafe.Pointer(&sliceHeader{s, len(s)}))
|
|
return Sum64(b)
|
|
}
|
|
|
|
// WriteString adds more data to d. It always returns len(s), nil.
|
|
// It may be faster than Write([]byte(s)) by avoiding a copy.
|
|
func (d *Digest) WriteString(s string) (n int, err error) {
|
|
d.Write(*(*[]byte)(unsafe.Pointer(&sliceHeader{s, len(s)})))
|
|
// d.Write always returns len(s), nil.
|
|
// Ignoring the return output and returning these fixed values buys a
|
|
// savings of 6 in the inliner's cost model.
|
|
return len(s), nil
|
|
}
|
|
|
|
// sliceHeader is similar to reflect.SliceHeader, but it assumes that the layout
|
|
// of the first two words is the same as the layout of a string.
|
|
type sliceHeader struct {
|
|
s string
|
|
cap int
|
|
}
|