Further fixes on single host installer deployment. No issue #

[arvados.git] / lib / crunchrun / background.go

diff --git a/lib/crunchrun/background.go b/lib/crunchrun/background.go
index 07f8f5b885d6dd2f7b87d7c16c75734880a9a7a0..adb65324b8bf339a1482c53656495dce50a3f0a6 100644 (file)
--- a/lib/crunchrun/background.go
+++ b/lib/crunchrun/background.go
@@ -21,6 +21,7 @@ var (
        lockprefix = "crunch-run-"
        locksuffix = ".lock"
        brokenfile = "crunch-run-broken"
+       pricesfile = "crunch-run-prices.json"
 )
 
 // procinfo is saved in each process's lockfile.
@@ -77,20 +78,24 @@ func detach(uuid string, prog string, args []string, stdin io.Reader, stdout io.
                // invoked as "/path/to/crunch-run"
                execargs = append([]string{prog}, execargs...)
        }
-       execargs = append([]string{
-               // Here, if the inner systemd-cat can't exec
-               // crunch-run, it writes an error message to stderr,
-               // and the outer systemd-cat writes it to the journal
-               // where the operator has a chance to discover it. (If
-               // we only used one systemd-cat command, it would be
-               // up to us to report the error -- but we are going to
-               // detach and exit, not wait for something to appear
-               // on stderr.)  Note these systemd-cat calls don't
-               // result in additional processes -- they just connect
-               // stderr/stdout to sockets and call exec().
-               "systemd-cat", "--identifier=crunch-run",
-               "systemd-cat", "--identifier=crunch-run",
-       }, execargs...)
+       if _, err := exec.LookPath("systemd-cat"); err == nil {
+               execargs = append([]string{
+                       // Here, if the inner systemd-cat can't exec
+                       // crunch-run, it writes an error message to
+                       // stderr, and the outer systemd-cat writes it
+                       // to the journal where the operator has a
+                       // chance to discover it. (If we only used one
+                       // systemd-cat command, it would be up to us
+                       // to report the error -- but we are going to
+                       // detach and exit, not wait for something to
+                       // appear on stderr.)  Note these systemd-cat
+                       // calls don't result in additional processes
+                       // -- they just connect stderr/stdout to
+                       // sockets and call exec().
+                       "systemd-cat", "--identifier=crunch-run",
+                       "systemd-cat", "--identifier=crunch-run",
+               }, execargs...)
+       }
 
        cmd := exec.Command(execargs[0], execargs[1:]...)
        // Child inherits lockfile.
@@ -179,7 +184,20 @@ func kill(uuid string, signal syscall.Signal, stdout, stderr io.Writer) error {
 }
 
 // ListProcesses lists UUIDs of active crunch-run processes.
-func ListProcesses(stdout, stderr io.Writer) int {
+func ListProcesses(stdin io.Reader, stdout, stderr io.Writer) int {
+       if buf, err := io.ReadAll(stdin); err == nil && len(buf) > 0 {
+               // write latest pricing data to disk where
+               // current/future crunch-run processes can load it
+               fnm := filepath.Join(lockdir, pricesfile)
+               fnmtmp := fmt.Sprintf("%s~%d", fnm, os.Getpid())
+               err := os.WriteFile(fnmtmp, buf, 0777)
+               if err != nil {
+                       fmt.Fprintf(stderr, "error writing price data to %s: %s", fnmtmp, err)
+               } else if err = os.Rename(fnmtmp, fnm); err != nil {
+                       fmt.Fprintf(stderr, "error renaming %s to %s: %s", fnmtmp, fnm, err)
+                       os.Remove(fnmtmp)
+               }
+       }
        // filepath.Walk does not follow symlinks, so we must walk
        // lockdir+"/." in case lockdir itself is a symlink.
        walkdir := lockdir + "/."
@@ -241,7 +259,7 @@ func ListProcesses(stdout, stderr io.Writer) int {
                        fmt.Fprintf(stderr, "%s: find process %d: %s", path, pi.PID, err)
                        return nil
                }
-               err = proc.Signal(syscall.Signal(0))
+               err = proc.Signal(syscall.SIGUSR2)
                if err != nil {
                        // Process is dead, even though lockfile was
                        // still locked. Most likely a stuck arv-mount