// convert the servicebuilder yaml file into a runit service directory
func (s *ServiceBuilder) stage(templates map[string]ServiceTemplate) error {
for serviceName, template := range templates {
stageDir := filepath.Join(s.StagingRoot, serviceName)
// create the default log directory
err := os.MkdirAll(filepath.Join(stageDir, "log"), 0755)
if err != nil {
return err
}
runScript, err := template.RunScript()
if err != nil {
return err
}
if _, err := util.WriteIfChanged(filepath.Join(stageDir, "run"), runScript, 0755); err != nil {
return err
}
logScript, err := template.LogScript()
if err != nil {
return err
}
if _, err := util.WriteIfChanged(filepath.Join(stageDir, "log", "run"), logScript, 0755); err != nil {
return err
}
}
return nil
}
// set the memory limit on a cgroup, 0 to unrestrict
// https://www.kernel.org/doc/Documentation/cgroups/memory.txt
func (subsys Subsystems) SetMemory(name string, bytes int) error {
if subsys.Memory == "" {
return UnsupportedError("memory")
}
softLimit := bytes
hardLimit := 2 * bytes
if hardLimit < softLimit {
// Deal with overflow
hardLimit = softLimit
}
if bytes == 0 {
softLimit = -1
hardLimit = -1
}
err := os.Mkdir(filepath.Join(subsys.Memory, name), 0755)
if err != nil && !os.IsExist(err) {
return err
}
// the hard memory limit must be set BEFORE the mem+swap limit
// so we must clear the swap limit at the start
err = ioutil.WriteFile(filepath.Join(subsys.Memory, name, "memory.memsw.limit_in_bytes"), []byte("-1\n"), 0)
if err != nil {
return err
}
_, err = util.WriteIfChanged(filepath.Join(subsys.Memory, name, "memory.soft_limit_in_bytes"), []byte(strconv.Itoa(softLimit)+"\n"), 0)
if err != nil {
return err
}
_, err = util.WriteIfChanged(filepath.Join(subsys.Memory, name, "memory.limit_in_bytes"), []byte(strconv.Itoa(hardLimit)+"\n"), 0)
if err != nil {
return err
}
_, err = util.WriteIfChanged(filepath.Join(subsys.Memory, name, "memory.memsw.limit_in_bytes"), []byte(strconv.Itoa(hardLimit)+"\n"), 0)
if err != nil {
return err
}
return nil
}
// set the number of logical CPUs in a given cgroup, 0 to unrestrict
// https://www.kernel.org/doc/Documentation/scheduler/sched-bwc.txt
func (subsys Subsystems) SetCPU(name string, cpus int) error {
if subsys.CPU == "" {
return UnsupportedError("cpu")
}
period := 1000000 // one million microseconds
quota := cpus * period
if cpus == 0 {
// one hundred thousand microseconds is the default, -1 will return EINVAL
period = 100000
// setting -1 here will unrestrict the cgroup, so the period won't matter
quota = -1
}
err := os.Mkdir(filepath.Join(subsys.CPU, name), 0755)
if err != nil && !os.IsExist(err) {
return err
}
_, err = util.WriteIfChanged(
filepath.Join(subsys.CPU, name, "cpu.cfs_period_us"),
[]byte(strconv.Itoa(period)+"\n"),
0,
)
if err != nil {
return err
}
_, err = util.WriteIfChanged(
filepath.Join(subsys.CPU, name, "cpu.cfs_quota_us"),
[]byte(strconv.Itoa(quota)+"\n"),
0,
)
if err != nil {
return err
}
return nil
}
// convert the servicebuilder yaml file into a runit service directory
func (s *ServiceBuilder) stage(templates map[string]ServiceTemplate, restartPolicy RestartPolicy) error {
nobody, err := user.Lookup("nobody")
if err != nil {
return err
}
nobodyUid, err := strconv.ParseInt(nobody.Uid, 10, 64)
if err != nil {
return err
}
nobodyGid, err := strconv.ParseInt(nobody.Gid, 10, 64)
if err != nil {
return err
}
for serviceName, template := range templates {
stageDir := filepath.Join(s.StagingRoot, serviceName)
// create the default log directory
logDir := filepath.Join(stageDir, "log")
err := os.MkdirAll(logDir, 0755)
if err != nil {
return err
}
// create a place for the logs to go
logMainDir := filepath.Join(logDir, "main")
err = os.Mkdir(logMainDir, 0755)
if err == nil {
if !s.testingNoChown {
err = os.Chown(logMainDir, int(nobodyUid), int(nobodyGid))
if err != nil {
return err
}
}
} else if !os.IsExist(err) {
return err
}
runScript, err := template.runScript()
if err != nil {
return err
}
if _, err := util.WriteIfChanged(filepath.Join(stageDir, "run"), runScript, 0755); err != nil {
return err
}
logScript, err := template.logScript()
if err != nil {
return err
}
if _, err := util.WriteIfChanged(filepath.Join(stageDir, "log", "run"), logScript, 0755); err != nil {
return err
}
finishScript, err := template.finishScript()
if err != nil {
return err
}
if _, err := util.WriteIfChanged(filepath.Join(stageDir, "finish"), finishScript, 0755); err != nil {
return err
}
// If a "down" file is not present, runit will restart the process
// whenever it finishes. Prevent that if the requested restart policy
// is not RestartAlways
downPath := filepath.Join(stageDir, DOWN_FILE_NAME)
if restartPolicy != RestartPolicyAlways {
file, err := os.Create(downPath)
if err != nil {
return err
}
_ = file.Close()
} else {
// There could be a down file lying around from a
// previous installation with a different restart
// policy, check for it and remove it if present
_, err := os.Stat(downPath)
if err == nil {
err := os.Remove(downPath)
if err != nil {
return util.Errorf("Unable to remove down file: %s", err)
}
} else if !os.IsNotExist(err) {
return util.Errorf("Error checking for down file: %s", err)
}
}
}
return nil
}
