os/exec: "fork/exec ... cannot allocate memory" on linux,!amd64 #31936
Description
What version of Go are you using (go version)?
$ go version go version devel +5286b2a Thu May 9 14:58:03 2019 +0000 linux/s390x
Does this issue reproduce with the latest release?
Yes.
What operating system and processor architecture are you using (go env)?
linux/s390x
What did you do?
On a linux/s390x LPAR with 12GB of RAM:
package main
import (
"log"
"os/exec"
)
func main() {
c := 8 * 1024 * 1024 * 1024
a := make([]byte, c, c)
for i := range a {
a[i] = byte(i % 255)
}
log.Print(exec.Command("sleep", "1").Run())
}$ go build -o fork fork.goWhat did you expect to see?
$ ./fork
2019/05/07 04:21:46 <nil>What did you see instead?
$ ./fork
2019/05/07 03:59:54 fork/exec /bin/sleep: cannot allocate memoryThis causes a production impact since various Go programs cannot fork/exec (including the Go compiler at times).
This is reproducable under Linux on most architectures aside from linux/amd64, where the problem has been addressed via issue #5838. The memory consumption will need to be altered depending on the available host memory.