# README

`bp`

bp implements buffer pool of various objects such as byte array ([]byte) or *bytes.Buffer / *image.RGBA and *bufio.Reader.
It is inspired by bpool and its many features are similar.

bp provides the following pool types

bp.BufferPool which provides fixed-size pool of *bytes.Buffers
bp.BytePool which provides fixed-size pool of []byte slice
bp.MmapBytePool Same as BytePool, but uses mmap to allocate the slices
bp.BufioReaderPool which provides fixed-size pool of *bufio.Reader
bp.BufioWriterPool which provides fixed-size pool of *bufio.Writer
bp.ImageRGBAPool which provides fixed-size pool of *image.RGBA
bp.ImageYCbCrPool which provides fixed-size pool of *image.YCbCr
bp.CopyIOPool which provides fixed-size pool of io.CopyBuffer and io.ReadAll
bp.TickerPool which provides fixed-size pool of *time.Ticker
bp.TimerPool which provides fixed-size pool of *time.Timer

It also provides a MultiPool to bundle multiple pools:

MultiBytePool
MultiMmapBytePool
MultiBufferPool
MultiImageRGBAPool
MultiImageYCbCrPool

In addition, bp provides an easy to manipulate object interface to prevent forgetting to put it back into the pool

bp.ByteRef
bp.BufferRef
bp.BufioReaderRef
bp.BufioWriterRef
bp.ImageRGBARef
bp.ImageYCbCrRef

Installation

go get github.com/octu0/bp

Example

Here's a quick example for using bp.BufferPool. We create a pool of the desired size, call the Get() method to obtain a buffer for use, and call Put(buf) to return the buffer to the pool.

var (
  bufpool := bp.NewBufferPool(1000, 128) // capacity 1000 items, each buffer initial 128 Byte pre-sized
)

func main() {
  // get buffer from pool
  buf := bufpool.Get()
  ...
  ...
  // return buffer to pool
  bufpool.Put(buf)
}

Benchmark

`bytes.Buffer`: sync.Pool vs BufferPool

$ go test -bench=BenchmarkBufferPool -benchmem ./
goos: darwin
goarch: amd64
pkg: github.com/octu0/bp
cpu: Intel(R) Core(TM) i7-8569U CPU @ 2.80GHz
BenchmarkBufferPool/default/8-8         	 1608904	       768.9 ns/op	      32 B/op	       1 allocs/op
BenchmarkBufferPool/default/4096-8      	 1421576	       791.1 ns/op	      32 B/op	       1 allocs/op
BenchmarkBufferPool/syncpool/8-8        	 1584180	       743.3 ns/op	      48 B/op	       1 allocs/op
BenchmarkBufferPool/syncpool/4096-8     	 1505594	       798.4 ns/op	      48 B/op	       1 allocs/op
BenchmarkBufferPool/bufferpool/8-8      	 1439310	       917.2 ns/op	      48 B/op	       1 allocs/op
BenchmarkBufferPool/bufferpool/4096-8   	 1225413	       967.4 ns/op	      48 B/op	       1 allocs/op
PASS
ok  	github.com/octu0/bp	12.309s

`[]byte`: sync.Pool vs BytePool

$ go test -bench=BenchmarkBytePool -benchmem ./
goos: darwin
goarch: amd64
pkg: github.com/octu0/bp
cpu: Intel(R) Core(TM) i7-8569U CPU @ 2.80GHz
BenchmarkBytePool/default/8-8         	 1827867	       653.8 ns/op	      16 B/op	       1 allocs/op
BenchmarkBytePool/default/4096-8      	 1562638	       788.3 ns/op	      16 B/op	       1 allocs/op
BenchmarkBytePool/syncpool/8-8        	 1643428	       763.2 ns/op	      48 B/op	       2 allocs/op
BenchmarkBytePool/syncpool/4096-8     	 1586283	       803.8 ns/op	      48 B/op	       2 allocs/op
BenchmarkBytePool/bytepool/8-8        	 1357020	       904.1 ns/op	      24 B/op	       1 allocs/op
BenchmarkBytePool/bytepool/4096-8     	 1359921	       846.6 ns/op	      24 B/op	       1 allocs/op
PASS
ok  	github.com/octu0/bp	12.105s

`bufio.Reader`: sync.Pool vs BufioReaderPool

$ go test -bench=BenchmarkBufioReaderPool -benchmem ./
goos: darwin
goarch: amd64
pkg: github.com/octu0/bp
cpu: Intel(R) Core(TM) i7-8569U CPU @ 2.80GHz
BenchmarkBufioReaderPool/default/8-8         	 1000000	      1120 ns/op	    1056 B/op	       3 allocs/op
BenchmarkBufioReaderPool/default/4096-8      	  803418	      1542 ns/op	    5136 B/op	       3 allocs/op
BenchmarkBufioReaderPool/syncpool/8-8        	 1000000	      1102 ns/op	    1048 B/op	       2 allocs/op
BenchmarkBufioReaderPool/syncpool/4096-8     	 1000000	      1110 ns/op	    1051 B/op	       2 allocs/op
BenchmarkBufioReaderPool/bufiopool/8-8       	 1000000	      1290 ns/op	    1160 B/op	       4 allocs/op
BenchmarkBufioReaderPool/bufiopool/4096-8    	  918162	      1279 ns/op	    1048 B/op	       2 allocs/op
PASS
ok  	github.com/octu0/bp	7.147s

`image.RGBA`: sync.Pool vs `ImageRGBAPool`

$ go test -bench=BenchmarkImageRGBAPool -benchmem ./
goos: darwin
goarch: amd64
pkg: github.com/octu0/bp
cpu: Intel(R) Core(TM) i7-8569U CPU @ 2.80GHz
BenchmarkImageRGBAPool/default/360-8         	   31308	     36206 ns/op	  925814 B/op	       3 allocs/op
BenchmarkImageRGBAPool/default/1080-8        	    4639	    821211 ns/op	 8282518 B/op	       3 allocs/op
BenchmarkImageRGBAPool/syncpool/360-8        	 1657608	       684.7 ns/op	      20 B/op	       1 allocs/op
BenchmarkImageRGBAPool/syncpool/1080-8       	 1635321	       696.2 ns/op	      56 B/op	       1 allocs/op
BenchmarkImageRGBAPool/imagepool/360-8       	 1000000	      1190 ns/op	     151 B/op	       3 allocs/op
BenchmarkImageRGBAPool/imagepool/1080-8      	 1000000	      1105 ns/op	     151 B/op	       3 allocs/op
PASS
ok  	github.com/octu0/bp	11.502s

io.Copy vs CopyIOPool.Copy Benchmark

CopyIOPool.Copy to reduce allocation of io.Copy

$ go test -bench=BenchmarkIoCopy -benchmem ./
goos: darwin
goarch: amd64
pkg: github.com/octu0/bp
cpu: Intel(R) Core(TM) i7-8569U CPU @ 2.80GHz
BenchmarkIoCopy-8                	  461892	      2637 ns/op	   32816 B/op	       3 allocs/op
BenchmarkIoCopyPoolDefault-8     	  619404	      1982 ns/op	   16608 B/op	       7 allocs/op
BenchmarkIoCopyPoolFixedSize-8   	 2858724	       410.9 ns/op	      48 B/op	       2 allocs/op
PASS
ok  	github.com/octu0/bp	4.126s

ioutil.ReadAll vs CopyIOPool.ReadAll Benchmark

similarly, CopyIOPool.ReadAll reduces allocation of io.ReadAll

$ go test -bench=BenchmarkIoReadAll -benchmem ./
goos: darwin
goarch: amd64
pkg: github.com/octu0/bp
cpu: Intel(R) Core(TM) i7-8569U CPU @ 2.80GHz
BenchmarkIoReadAllIoUtil-8          	    2628	    455815 ns/op	 5862972 B/op	      30 allocs/op
BenchmarkIoReadAllPoolDefault-8     	    3057	    378599 ns/op	 4063444 B/op	      13 allocs/op
BenchmarkIoReadAllPoolFixedSize-8   	    3180	    378923 ns/op	 4046892 B/op	       8 allocs/op
PASS
ok  	github.com/octu0/bp	3.718s

`*time.Ticker`: sync.Pool vs `TickerPool`

$ go test -bench=BenchmarkTickerPool -benchmem ./
goos: darwin
goarch: amd64
pkg: github.com/octu0/bp
cpu: Intel(R) Core(TM) i7-8569U CPU @ 2.80GHz
BenchmarkTickerPool/default-8         	  114298	     10731 ns/op	     224 B/op	       4 allocs/op
BenchmarkTickerPool/syncpool-8        	  110748	     10863 ns/op	      32 B/op	       1 allocs/op
BenchmarkTickerPool/pool-8            	  110414	     10867 ns/op	      32 B/op	       1 allocs/op
PASS
ok  	github.com/octu0/bp	3.994s

`*time.Timer`: sync.Pool vs `TimerPool`

$ go test -bench=BenchmarkTimerPool -benchmem ./
goos: darwin
goarch: amd64
pkg: github.com/octu0/bp
cpu: Intel(R) Core(TM) i7-8569U CPU @ 2.80GHz
BenchmarkTimerPool/default-8         	  115437	     10889 ns/op	     224 B/op	       4 allocs/op
BenchmarkTimerPool/syncpool-8        	  107302	     11099 ns/op	      32 B/op	       1 allocs/op
BenchmarkTimerPool/pool-8            	  106790	     11061 ns/op	      32 B/op	       1 allocs/op
PASS
ok  	github.com/octu0/bp	4.002s