services/keep-web/writebuffer_test.go

   1 // Copyright (C) The Arvados Authors. All rights reserved.
   2 //
   3 // SPDX-License-Identifier: AGPL-3.0
   4
   5 package keepweb
   6
   7 import (
   8         "bytes"
   9         "io"
  10         "math/rand"
  11         "time"
  12
  13         . "gopkg.in/check.v1"
  14 )
  15
  16 var _ = Suite(&writeBufferSuite{})
  17
  18 type writeBufferSuite struct {
  19 }
  20
  21 // 1000 / 96.3 ns/op = 10.384 GB/s
  22 func (s *writeBufferSuite) Benchmark_1KBWrites(c *C) {
  23         wb := newWriteBuffer(io.Discard, 1<<20)
  24         in := make([]byte, 1000)
  25         for i := 0; i < c.N; i++ {
  26                 wb.Write(in)
  27         }
  28         wb.Close()
  29 }
  30
  31 func (s *writeBufferSuite) TestRandomizedSpeedsAndSizes(c *C) {
  32         for i := 0; i < 20; i++ {
  33                 insize := rand.Intn(1 << 26)
  34                 bufsize := rand.Intn(1 << 26)
  35                 if i < 2 {
  36                         // make sure to test edge cases
  37                         bufsize = i
  38                 } else if insize/bufsize > 1000 {
  39                         // don't waste too much time testing tiny
  40                         // buffer / huge content
  41                         insize = bufsize*1000 + 123
  42                 }
  43                 c.Logf("%s: insize %d bufsize %d", c.TestName(), insize, bufsize)
  44
  45                 in := make([]byte, insize)
  46                 b := byte(0)
  47                 for i := range in {
  48                         in[i] = b
  49                         b++
  50                 }
  51
  52                 out := &bytes.Buffer{}
  53                 done := make(chan struct{})
  54                 pr, pw := io.Pipe()
  55                 go func() {
  56                         n, err := slowCopy(out, pr, rand.Intn(8192)+1)
  57                         c.Check(err, IsNil)
  58                         c.Check(n, Equals, int64(insize))
  59                         close(done)
  60                 }()
  61                 wb := newWriteBuffer(pw, bufsize)
  62                 n, err := slowCopy(wb, bytes.NewBuffer(in), rand.Intn(8192)+1)
  63                 c.Check(err, IsNil)
  64                 c.Check(n, Equals, int64(insize))
  65                 c.Check(wb.Close(), IsNil)
  66                 c.Check(pw.Close(), IsNil)
  67                 <-done
  68                 c.Check(out.Len(), Equals, insize)
  69                 for i := 0; i < out.Len() && i < len(in); i++ {
  70                         if out.Bytes()[i] != in[i] {
  71                                 c.Errorf("content mismatch at byte %d", i)
  72                                 break
  73                         }
  74                 }
  75         }
  76 }
  77
  78 func slowCopy(dst io.Writer, src io.Reader, bufsize int) (int64, error) {
  79         wrote := int64(0)
  80         buf := make([]byte, bufsize)
  81         for {
  82                 time.Sleep(time.Duration(rand.Intn(100) + 1))
  83                 n, err := src.Read(buf)
  84                 if n > 0 {
  85                         n, err := dst.Write(buf[:n])
  86                         wrote += int64(n)
  87                         if err != nil {
  88                                 return wrote, err
  89                         }
  90                 }
  91                 if err == io.EOF {
  92                         return wrote, nil
  93                 }
  94                 if err != nil {
  95                         return wrote, err
  96                 }
  97         }
  98 }