README
¶
pbytes
The initial code cloned from https://github.com/gobwas/pool
Problem
If you try to assign a []byte to an interface{}, the compiler will generate additional conversion code runtime.convTslice and cause memory allocation.
func main() {
buffer := make([]byte, 0, 64)
var o interface{} = buffer // CALL runtime.convTslice(SB)
fmt.Println(o)
}
convTslice source code https://go.dev/src/runtime/iface.go
func convTslice(val []byte) (x unsafe.Pointer) {
// Note: this must work for any element type, not just byte.
if (*slice)(unsafe.Pointer(&val)).array == nil {
x = unsafe.Pointer(&zeroVal[0])
} else {
x = mallocgc(unsafe.Sizeof(val), sliceType, true)
*(*[]byte)(x) = val
}
return
}
(*sync.Pool).Put source code https://go.dev/src/sync/pool.go
// Put adds x to the pool
func (p *Pool) Put(x any) {
...
}
var buf = make([]byte, 0, 16)
// equals:
// var x interface{} = buf // CALL runtime.convTslice(SB)
// pool.Put(x)
pool.Put(buf)
Resolved
Don't put the []byte into sync.Pool, to resolve the problems, put *[]byte instead.
Documentation
¶
Overview ¶
Package pool contains helpers for pooling structures distinguishable by size.
Quick example:
import "github.com/gobwas/pool"
func main() {
// Reuse objects in logarithmic range from 0 to 64 (0,1,2,4,6,8,16,32,64).
p := pool.New(0, 64)
buf, n := p.Get(10) // Returns buffer with 16 capacity.
if buf == nil {
buf = bytes.NewBuffer(make([]byte, n))
}
defer p.Put(buf, n)
// Work with buf.
}
There are non-generic implementations for pooling: - pool/pbytes for []byte reuse; - pool/pbufio for *bufio.Reader and *bufio.Writer reuse;
Index ¶
Constants ¶
This section is empty.
Variables ¶
This section is empty.
Functions ¶
This section is empty.
Types ¶
type Option ¶
type Option func(Config)
Option configures pool.
func WithIdentitySizeMapping ¶
func WithIdentitySizeMapping() Option
func WithLogSizeMapping ¶
func WithLogSizeMapping() Option
func WithLogSizeRange ¶
WithSizeLogRange returns an Option that will add logarithmic range of pooling sizes containing [min, max] values.
func WithSizeMapping ¶
type Pool ¶
type Pool struct {
// contains filtered or unexported fields
}
Pool contains logic of reusing objects distinguishable by size in generic way.
func New ¶
New creates new Pool that reuses objects which size is in logarithmic range [min, max].
Note that it is a shortcut for Custom() constructor with Options provided by WithLogSizeMapping() and WithLogSizeRange(min, max) calls.
Source Files
Directories