parallel	= flag.Int("test.parallel", runtime.GOMAXPROCS(0), "maximum test parallelism")
	
		cpuList	[]int
	)

	// 
	var benchTime = flag.Duration("test.benchtime", 1*time.Second, "approximate run time for each benchmark")

	// 
	var matchBenchmarks = flag.String("test.bench", "", "regular expression to select benchmarks to run")

	// 
	var timer *time.Timer

// cache for N concurrent tokens?"
//
// Given the size of the key range constructed by this test, the default go
// benchtime of 1 second is often inadequate to test caching and expiration
// behavior. A benchtime of 10 to 30 seconds is adequate to stress these
// code paths.
type singleBenchmark struct {
	threadCount int
	// These token.* variables are set by makeTokens()

			// This is almost like the Benchmark function, except that we override
			// the benchtime and catch the failure result of the subbenchmark.
			root := &B{
				common: common{
					signal: make(chan bool),
					name:   "root",
					w:      buf,
				},
				benchFunc: func(b *B) { ok = b.Run("test", tc.f) }, // Use Run to catch failure.
				benchTime: durationOrCountFlag{d: 1 * time.Microsecond},
			}
			if tc.chatty {

		fmt.Println(index, " : update time : ", elapsed, "commit time : ", elapsed2,
			"\n1000 Get time : ", elapsed3,
			"\nRAM : ", m.Sys/1024/1024, " MiB")
	}
}

// go test -run=xxx -bench=. -benchmem -test.benchtime=20s
func BenchmarkCacheHeightLimit(b *testing.B) {
	smt := newSMT(hasher, cache.NewTTL(forever, time.Minute), time.Minute)
	benchmark10MAccounts10Ktps(smt, b)

	// to build the test in a way that supports the use of the flag.

	cf.StringVar(&testBench, "bench", "", "")
	cf.Bool("benchmem", false, "")
	cf.String("benchtime", "", "")
	cf.StringVar(&testBlockProfile, "blockprofile", "", "")
	cf.String("blockprofilerate", "", "")
	cf.Int("count", 0, "")
	cf.String("cpu", "", "")
	cf.StringVar(&testCPUProfile, "cpuprofile", "", "")

	    with b.N=1 to find any sub-benchmarks matching Y, which are
	    then run in full.

	-benchtime t
	    Run enough iterations of each benchmark to take t, specified
	    as a time.Duration (for example, -benchtime 1h30s).
	    The default is 1 second (1s).
	    The special syntax Nx means to run the benchmark N times
	    (for example, -benchtime 100x).

	-count n
	    Run each test, benchmark, and fuzz seed n times (default 1).

	exe, err := os.Executable()
	if err != nil {
		t.Skipf("can't find test executable: %v", err)
	}

	cmd := testenv.Command(t, exe, "-test.run=^"+test+"$", "-test.bench="+test, "-test.v", "-test.parallel=2", "-test.benchtime=2x")
	cmd = testenv.CleanCmdEnv(cmd)
	cmd.Env = append(cmd.Env, "GO_WANT_HELPER_PROCESS=1")
	out, err := cmd.CombinedOutput()
	t.Logf("%v: %v\n%s", cmd, err, out)

	return out
}

//	    then run in full.
//
//	-benchtime t
//	    Run enough iterations of each benchmark to take t, specified
//	    as a time.Duration (for example, -benchtime 1h30s).
//	    The default is 1 second (1s).
//	    The special syntax Nx means to run the benchmark N times
//	    (for example, -benchtime 100x).
//
//	-count n

	}
	if t.asan {
		build = append(build, "-asan")
	}
	if opts.bench {
		// Run no tests.
		run = append(run, "-run=^$")
		// Run benchmarks briefly as a smoke test.
		run = append(run, "-bench=.*", "-benchtime=.1s")
	} else if opts.runTests != "" {
		run = append(run, "-run="+opts.runTests)
	}
	if opts.cpu != "" {
		run = append(run, "-cpu="+opts.cpu)
	}
	if t.json {
		run = append(run, "-json")
	}

	Family    uint16
	Pad_cgo_0 [2]byte
	Flags     int32
	Len       int32
	Pad_cgo_1 [4]byte
	Lifcu     [8]byte
}

type lifIfinfoReq struct {
	Maxhops      uint8
	Pad_cgo_0    [3]byte
	Reachtime    uint32
	Reachretrans uint32
	Maxmtu       uint32