3826: Add host-level network IO monitoring, and placeholder for task-level.

diff --git a/services/crunchstat/crunchstat.go b/services/crunchstat/crunchstat.go
index 9175cf0ba2858ba85d421cc304ffa67e5ea2658c..0d279063af9aec1383cc6f06fa10d121f00c3d47 100644 (file)
--- a/services/crunchstat/crunchstat.go
+++ b/services/crunchstat/crunchstat.go
@@ -56,25 +56,91 @@ func OpenAndReadAll(filename string, log_chan chan<- string) ([]byte, error) {
        }
 }
 
-func FindStat(cgroup_root string, cgroup_parent string, container_id string, statgroup string, stat string) string {
+func FindStat(stderr chan<- string, cgroup_root string, cgroup_parent string, container_id string, statgroup string, stat string) string {
        var path string
-       path = fmt.Sprintf("%s/%s/%s/%s/%s.%s", cgroup_root, statgroup, cgroup_parent, container_id, statgroup, stat)
-       if _, err := os.Stat(path); err == nil {
-               return path
+       path = fmt.Sprintf("%s/%s/%s/%s/%s", cgroup_root, statgroup, cgroup_parent, container_id, stat)
+       if _, err := os.Stat(path); err != nil {
+               path = fmt.Sprintf("%s/%s/%s/%s", cgroup_root, cgroup_parent, container_id, stat)
        }
-       path = fmt.Sprintf("%s/%s/%s/%s.%s", cgroup_root, cgroup_parent, container_id, statgroup, stat)
-       if _, err := os.Stat(path); err == nil {
-               return path
+       if _, err := os.Stat(path); err != nil {
+               path = fmt.Sprintf("%s/%s/%s", cgroup_root, statgroup, stat)
        }
-       path = fmt.Sprintf("%s/%s/%s.%s", cgroup_root, statgroup, statgroup, stat)
-       if _, err := os.Stat(path); err == nil {
-               return path
+       if _, err := os.Stat(path); err != nil {
+               path = fmt.Sprintf("%s/%s", cgroup_root, stat)
        }
-       path = fmt.Sprintf("%s/%s.%s", cgroup_root, statgroup, stat)
-       if _, err := os.Stat(path); err == nil {
-               return path
+       if _, err := os.Stat(path); err != nil {
+               stderr <- fmt.Sprintf("crunchstat: did not find stats file (root %s, parent %s, cid %s, statgroup %s, stat %s)", cgroup_root, cgroup_parent, container_id, statgroup, stat)
+               return ""
        }
-       return ""
+       stderr <- fmt.Sprintf("crunchstat: reading stats from %s", path)
+       return path
+}
+
+func SetNetworkNamespace(stderr chan<- string, procsFilename string) (string) {
+       // Not supported yet -- we'll just report host-wide network stats.
+       return "host"
+
+       if procsFilename == "" { return "host" }
+       procsFile, err := os.Open(procsFilename)
+       if err != nil {
+               stderr <- fmt.Sprintf("crunchstat: open %s: %s", procsFilename, err)
+               return "host"
+       }
+       defer procsFile.Close()
+       reader := bufio.NewScanner(procsFile)
+       for reader.Scan() {
+               taskPid := reader.Text()
+               netnsFilename := fmt.Sprintf("/proc/%s/ns/net", taskPid)
+               netnsFile, err := os.Open(netnsFilename)
+               if err != nil {
+                       stderr <- fmt.Sprintf("crunchstat: open %s: %s", netnsFilename, err)
+                       continue
+               }
+               defer netnsFile.Close()
+
+               // syscall.Setns() doesn't exist yet, and doesn't work
+               // from a multithreaded program yet.
+               //
+               // if _, err2 := syscall.Setns(netnsFile.Fd()); err != nil {
+               //      stderr <- fmt.Sprintf("crunchstat: Setns: %s", err2)
+               //      continue
+               // }
+               return "task"
+       }
+       return "host"
+}
+
+type NetStat struct {
+       tx_bytes int64
+       rx_bytes int64
+}
+func DoNetworkStats(stderr chan<- string, procsFilename string, lastStat *NetStat, elapsed float64) (*NetStat) {
+       statScope := SetNetworkNamespace(stderr, procsFilename)
+
+       ifName := "eth0"
+       tx_s, tx_err := OpenAndReadAll(fmt.Sprintf("/sys/class/net/%s/statistics/tx_bytes", ifName), stderr)
+       rx_s, rx_err := OpenAndReadAll(fmt.Sprintf("/sys/class/net/%s/statistics/rx_bytes", ifName), stderr)
+       if rx_err != nil || tx_err != nil {
+               return nil
+       }
+       nextStat := new(NetStat)
+       fmt.Sscanf(string(tx_s), "%d", &nextStat.tx_bytes)
+       fmt.Sscanf(string(rx_s), "%d", &nextStat.rx_bytes)
+       if lastStat != nil {
+               stderr <- fmt.Sprintf("crunchstat: %s net %s tx %d rx %d interval %.4f",
+                       statScope,
+                       ifName,
+                       nextStat.tx_bytes - lastStat.tx_bytes,
+                       nextStat.rx_bytes - lastStat.rx_bytes,
+                       elapsed)
+       }
+       return nextStat
+}
+
+type Cgroup struct {
+       cgroup_root   string
+       cgroup_parent string
+       container_id  string
 }
 
 func PollCgroupStats(cgroup_root string, cgroup_parent string, container_id string, stderr chan string, poll int64, stop_poll_chan <-chan bool) {
@@ -93,23 +159,12 @@ func PollCgroupStats(cgroup_root string, cgroup_parent string, container_id stri
 
        user_hz := float64(C.sysconf(C._SC_CLK_TCK))
 
-       cpuacct_stat := FindStat(cgroup_root, cgroup_parent, container_id, "cpuacct", "stat")
-       blkio_io_service_bytes := FindStat(cgroup_root, cgroup_parent, container_id, "blkio", "io_service_bytes")
-       cpuset_cpus := FindStat(cgroup_root, cgroup_parent, container_id, "cpuset", "cpus")
-       memory_stat := FindStat(cgroup_root, cgroup_parent, container_id, "memory", "stat")
-
-       if cpuacct_stat != "" {
-               stderr <- fmt.Sprintf("crunchstat: reading stats from %s", cpuacct_stat)
-       }
-       if blkio_io_service_bytes != "" {
-               stderr <- fmt.Sprintf("crunchstat: reading stats from %s", blkio_io_service_bytes)
-       }
-       if cpuset_cpus != "" {
-               stderr <- fmt.Sprintf("crunchstat: reading stats from %s", cpuset_cpus)
-       }
-       if memory_stat != "" {
-               stderr <- fmt.Sprintf("crunchstat: reading stats from %s", memory_stat)
-       }
+       cpuacct_stat := FindStat(stderr, cgroup_root, cgroup_parent, container_id, "cpuacct", "cpuacct.stat")
+       blkio_io_service_bytes := FindStat(stderr, cgroup_root, cgroup_parent, container_id, "blkio", "blkio.io_service_bytes")
+       cpuset_cpus := FindStat(stderr, cgroup_root, cgroup_parent, container_id, "cpuset", "cpuset.cpus")
+       memory_stat := FindStat(stderr, cgroup_root, cgroup_parent, container_id, "memory", "memory.stat")
+       procs := FindStat(stderr, cgroup_root, cgroup_parent, container_id, "cpuacct", "cgroup.procs")
+       lastNetStat := DoNetworkStats(stderr, procs, nil, 0)
 
        poll_chan := make(chan bool, 1)
        go func() {
@@ -238,6 +293,8 @@ func PollCgroupStats(cgroup_root string, cgroup_parent string, container_id stri
                        }
                        c.Close()
                }
+
+               lastNetStat = DoNetworkStats(stderr, procs, lastNetStat, elapsed)
        }
 }