The code below implements a simple timer loop that doubles the amount of time it waits (up to a max) after each firing. It works fine on my x86 linux box, but behaves erratically on a Raspberry Pi ARM platform (and on the playground).
I'm assuming I'm doing something bad, but it isn't clear at all to me what I'm missing. Code on playground and below, as well as machine specs and output. What is going on? // https://play.golang.org/p/8hN9pR6LlU package main import ( "fmt" "time" ) func main() { scale := 2 max := 15 * time.Second currDur := 250 * time.Millisecond tick := time.After(currDur) prev := time.Now() for i := 1; i <= 10; i++ { select { case t := <-tick: now := time.Now() delta := now.Sub(prev) prev = now fmt.Printf("%2d: %s %s\n", i, delta, t) currDur = time.Duration(int(currDur) * scale) if currDur >= max { currDur = max } tick = time.After(currDur) } } return } /* -------------------- Host for cross compile mke% go version go version go1.7.3 linux/amd64 mke% lsb_release -a No LSB modules are available. Distributor ID:Ubuntu Description:Ubuntu 14.04.5 LTS Release:14.04 Codename:trusty mke% uname -a Linux mke 4.2.0-42-generic #49~14.04.1-Ubuntu SMP Wed Jun 29 20:22:11 UTC 2016 \ x86_64 x86_64 x86_64 GNU/Linux # compile native mke% go build tryit.go # cross-compile mke% GOOS=linux GOARCH=arm go build tryit.go mke% ./tryit 1: 250.192493ms 2017-01-11 14:07:12.041348721 -0500 EST 2: 500.386557ms 2017-01-11 14:07:12.541735315 -0500 EST 3: 1.000226231s 2017-01-11 14:07:13.541964105 -0500 EST 4: 2.000227623s 2017-01-11 14:07:15.542191833 -0500 EST 5: 4.000226419s 2017-01-11 14:07:19.542417936 -0500 EST 6: 8.000232073s 2017-01-11 14:07:27.542649813 -0500 EST 7: 15.000257032s 2017-01-11 14:07:42.542907276 -0500 EST 8: 15.000299935s 2017-01-11 14:07:57.543207607 -0500 EST 9: 15.000226352s 2017-01-11 14:08:12.543433699 -0500 EST 10: 15.000233635s 2017-01-11 14:08:27.543667311 -0500 EST -------------------- Target machine (Raspberry Pi 3 B) pi3% lsb_release -a No LSB modules are available. Distributor ID:Raspbian Description:Raspbian GNU/Linux 8.0 (jessie) Release:8.0 Codename:jessie pi3% uname -a Linux art-pi3 4.4.11-v7+ #888 SMP Mon May 23 20:10:33 BST 2016 armv7l GNU/Linux pi3% ./tryit 1: 250.18908ms 2017-01-11 14:22:36.294351503 -0500 EST 2: 501.487843ms 2017-01-11 14:22:36.795825492 -0500 EST 3: 1.000988352s 2017-01-11 14:22:37.796819 -0500 EST 4: 2.000598851s 2017-01-11 14:22:39.79741155 -0500 EST 5: 440.832us 2017-01-11 14:22:39.797884724 -0500 EST 6: 292.394us 2017-01-11 14:22:39.798177848 -0500 EST 7: 266.196us 2017-01-11 14:22:39.798443888 -0500 EST 8: 1.935652004s 2017-01-11 14:22:41.734063912 -0500 EST 9: 458.539us 2017-01-11 14:22:41.734553753 -0500 EST 10: 267.29us 2017-01-11 14:22:41.734821408 -0500 EST */ -- You received this message because you are subscribed to the Google Groups "golang-nuts" group. To unsubscribe from this group and stop receiving emails from it, send an email to golang-nuts+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
