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Forked from j33ty/print-memory.go
Created February 7, 2022 23:51
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Go print current memory
package main
import (
"runtime"
"fmt"
"time"
)
func main() {
// Print our starting memory usage (should be around 0mb)
PrintMemUsage()
var overall [][]int
for i := 0; i<4; i++ {
// Allocate memory using make() and append to overall (so it doesn't get
// garbage collected). This is to create an ever increasing memory usage
// which we can track. We're just using []int as an example.
a := make([]int, 0, 999999)
overall = append(overall, a)
// Print our memory usage at each interval
PrintMemUsage()
time.Sleep(time.Second)
}
// Clear our memory and print usage, unless the GC has run 'Alloc' will remain the same
overall = nil
PrintMemUsage()
// Force GC to clear up, should see a memory drop
runtime.GC()
PrintMemUsage()
}
// PrintMemUsage outputs the current, total and OS memory being used. As well as the number
// of garage collection cycles completed.
func PrintMemUsage() {
var m runtime.MemStats
runtime.ReadMemStats(&m)
// For info on each, see: https://golang.org/pkg/runtime/#MemStats
fmt.Printf("Alloc = %v MiB", bToMb(m.Alloc))
fmt.Printf("\tTotalAlloc = %v MiB", bToMb(m.TotalAlloc))
fmt.Printf("\tSys = %v MiB", bToMb(m.Sys))
fmt.Printf("\tNumGC = %v\n", m.NumGC)
}
func bToMb(b uint64) uint64 {
return b / 1024 / 1024
}
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