| // Copyright 2015 The Go Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style |
| // license that can be found in the LICENSE file. |
| |
| package main |
| |
| import ( |
| "fmt" |
| "os" |
| "runtime" |
| "time" |
| ) |
| |
| func init() { |
| register("GCFairness", GCFairness) |
| register("GCSys", GCSys) |
| } |
| |
| func GCSys() { |
| runtime.GOMAXPROCS(1) |
| memstats := new(runtime.MemStats) |
| runtime.GC() |
| runtime.ReadMemStats(memstats) |
| sys := memstats.Sys |
| |
| runtime.MemProfileRate = 0 // disable profiler |
| |
| itercount := 100000 |
| for i := 0; i < itercount; i++ { |
| workthegc() |
| } |
| |
| // Should only be using a few MB. |
| // We allocated 100 MB or (if not short) 1 GB. |
| runtime.ReadMemStats(memstats) |
| if sys > memstats.Sys { |
| sys = 0 |
| } else { |
| sys = memstats.Sys - sys |
| } |
| if sys > 16<<20 { |
| fmt.Printf("using too much memory: %d bytes\n", sys) |
| return |
| } |
| fmt.Printf("OK\n") |
| } |
| |
| func workthegc() []byte { |
| return make([]byte, 1029) |
| } |
| |
| func GCFairness() { |
| runtime.GOMAXPROCS(1) |
| f, err := os.Open("/dev/null") |
| if os.IsNotExist(err) { |
| // This test tests what it is intended to test only if writes are fast. |
| // If there is no /dev/null, we just don't execute the test. |
| fmt.Println("OK") |
| return |
| } |
| if err != nil { |
| fmt.Println(err) |
| os.Exit(1) |
| } |
| for i := 0; i < 2; i++ { |
| go func() { |
| for { |
| f.Write([]byte(".")) |
| } |
| }() |
| } |
| time.Sleep(10 * time.Millisecond) |
| fmt.Println("OK") |
| } |
