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| author | Austin Clements <austin@google.com> | 2016-12-24 17:03:10 -0800 |
|---|---|---|
| committer | Austin Clements <austin@google.com> | 2017-01-08 00:01:30 +0000 |
| commit | ffedff7e506cdf298f06ad36f3264ca197aa7d25 (patch) | |
| tree | e451c2b68ec17ca4b470ab332825083eea749c12 | |
| parent | 3156736189dbc4e4a4a955c78334590819c9a914 (diff) | |
| download | go-ffedff7e506cdf298f06ad36f3264ca197aa7d25.tar.gz go-ffedff7e506cdf298f06ad36f3264ca197aa7d25.zip | |
runtime: add table of size classes in a comment
Change-Id: I52fae67c9aeceaa23e70f2ef0468745b354f8c75
Reviewed-on: https://go-review.googlesource.com/34932
Reviewed-by: Minux Ma <minux@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
| -rw-r--r-- | src/runtime/mksizeclasses.go | 16 | ||||
| -rw-r--r-- | src/runtime/sizeclasses.go | 68 |
2 files changed, 84 insertions, 0 deletions
diff --git a/src/runtime/mksizeclasses.go b/src/runtime/mksizeclasses.go index 587d3c77a1..0f897ba8e6 100644 --- a/src/runtime/mksizeclasses.go +++ b/src/runtime/mksizeclasses.go @@ -54,6 +54,8 @@ func main() { fmt.Fprintln(&b, "package runtime") classes := makeClasses() + printComment(&b, classes) + printClasses(&b, classes) out, err := format.Source(b.Bytes()) @@ -239,6 +241,20 @@ nextk: } } +func printComment(w io.Writer, classes []class) { + fmt.Fprintf(w, "// %-5s %-9s %-10s %-7s %-11s\n", "class", "bytes/obj", "bytes/span", "objects", "waste bytes") + for i, c := range classes { + if i == 0 { + continue + } + spanSize := c.npages * pageSize + objects := spanSize / c.size + waste := spanSize - c.size*(spanSize/c.size) + fmt.Fprintf(w, "// %5d %9d %10d %7d %11d\n", i, c.size, spanSize, objects, waste) + } + fmt.Fprintf(w, "\n") +} + func printClasses(w io.Writer, classes []class) { fmt.Fprintln(w, "const (") fmt.Fprintf(w, "_MaxSmallSize = %d\n", maxSmallSize) diff --git a/src/runtime/sizeclasses.go b/src/runtime/sizeclasses.go index ec30d15d36..e616e95148 100644 --- a/src/runtime/sizeclasses.go +++ b/src/runtime/sizeclasses.go @@ -3,6 +3,74 @@ package runtime +// class bytes/obj bytes/span objects waste bytes +// 1 8 8192 1024 0 +// 2 16 8192 512 0 +// 3 32 8192 256 0 +// 4 48 8192 170 32 +// 5 64 8192 128 0 +// 6 80 8192 102 32 +// 7 96 8192 85 32 +// 8 112 8192 73 16 +// 9 128 8192 64 0 +// 10 144 8192 56 128 +// 11 160 8192 51 32 +// 12 176 8192 46 96 +// 13 192 8192 42 128 +// 14 208 8192 39 80 +// 15 224 8192 36 128 +// 16 240 8192 34 32 +// 17 256 8192 32 0 +// 18 288 8192 28 128 +// 19 320 8192 25 192 +// 20 352 8192 23 96 +// 21 384 8192 21 128 +// 22 416 8192 19 288 +// 23 448 8192 18 128 +// 24 480 8192 17 32 +// 25 512 8192 16 0 +// 26 576 8192 14 128 +// 27 640 8192 12 512 +// 28 704 8192 11 448 +// 29 768 8192 10 512 +// 30 896 8192 9 128 +// 31 1024 8192 8 0 +// 32 1152 8192 7 128 +// 33 1280 8192 6 512 +// 34 1408 16384 11 896 +// 35 1536 8192 5 512 +// 36 1792 16384 9 256 +// 37 2048 8192 4 0 +// 38 2304 16384 7 256 +// 39 2688 8192 3 128 +// 40 3072 24576 8 0 +// 41 3200 16384 5 384 +// 42 3456 24576 7 384 +// 43 4096 8192 2 0 +// 44 4864 24576 5 256 +// 45 5376 16384 3 256 +// 46 6144 24576 4 0 +// 47 6528 32768 5 128 +// 48 6784 40960 6 256 +// 49 6912 49152 7 768 +// 50 8192 8192 1 0 +// 51 9472 57344 6 512 +// 52 9728 49152 5 512 +// 53 10240 40960 4 0 +// 54 10880 32768 3 128 +// 55 12288 24576 2 0 +// 56 13568 40960 3 256 +// 57 14336 57344 4 0 +// 58 16384 16384 1 0 +// 59 18432 73728 4 0 +// 60 19072 57344 3 128 +// 61 20480 40960 2 0 +// 62 21760 65536 3 256 +// 63 24576 24576 1 0 +// 64 27264 81920 3 128 +// 65 28672 57344 2 0 +// 66 32768 32768 1 0 + const ( _MaxSmallSize = 32768 smallSizeDiv = 8 |