iotop: fix bytes per second, and add accumulation

Bytes per second forgot to divide bytes by seconds.  Also add
the -a flag to print bytes instead of bytes per second.

Change-Id: I419b2ec0f702a291d299fe736d2d4ab290c03445

Author: colincross

iotop/iotop.cpp

@@ -41,6 +41,7 @@ static float TimeToTgidPercent(uint64_t ns, int time, const TaskStatistics& stat
 static void usage(char* myname) {
   printf(
       "Usage: %s [-h] [-P] [-d <delay>] [-n <cycles>] [-s <column>]\n"
+      "   -a  Show byte count instead of rate\n"
       "   -d  Set the delay between refreshes in seconds.\n"
       "   -h  Display this help screen.\n"
       "   -m  Set the number of processes or threads to show\n"
@@ -97,6 +98,7 @@ static Sorter GetSorter(const std::string field) {
 }
 
 int main(int argc, char* argv[]) {
+  bool accumulated = false;
   bool processes = false;
   int delay = 1;
   int cycles = -1;
@@ -108,6 +110,7 @@ int main(int argc, char* argv[]) {
   while (1) {
     int c;
     static const option longopts[] = {
+        {"accumulated", 0, 0, 'a'},
         {"delay", required_argument, 0, 'd'},
         {"help", 0, 0, 'h'},
         {"limit", required_argument, 0, 'm'},
@@ -116,11 +119,14 @@ int main(int argc, char* argv[]) {
         {"processes", 0, 0, 'P'},
         {0, 0, 0, 0},
     };
-    c = getopt_long(argc, argv, "d:hm:n:Ps:", longopts, NULL);
+    c = getopt_long(argc, argv, "ad:hm:n:Ps:", longopts, NULL);
     if (c < 0) {
       break;
     }
     switch (c) {
+    case 'a':
+      accumulated = true;
+      break;
     case 'd':
       delay = atoi(optarg);
       break;
@@ -213,8 +219,13 @@ int main(int argc, char* argv[]) {
       if (!second) {
         printf("\n");
       }
-      printf("%6s %-16s %20s %34s\n", "", "",
-          "--- IO (KiB/s) ---", "----------- delayed on ----------");
+      if (accumulated) {
+        printf("%6s %-16s %20s %34s\n", "", "",
+            "---- IO (KiB) ----", "----------- delayed on ----------");
+      } else {
+        printf("%6s %-16s %20s %34s\n", "", "",
+            "--- IO (KiB/s) ---", "----------- delayed on ----------");
+      }
       printf("%6s %-16s %6s %6s %6s  %-5s  %-5s  %-5s  %-5s  %-5s\n",
           "PID",
           "Command",
@@ -228,12 +239,13 @@ int main(int argc, char* argv[]) {
           "total");
       int n = limit;
       for (const TaskStatistics& statistics : stats) {
+        const int delay_div = accumulated ? 1 : delay;
         printf("%6d %-16s %6" PRIu64 " %6" PRIu64 " %6" PRIu64 " %5.2f%% %5.2f%% %5.2f%% %5.2f%% %5.2f%%\n",
             statistics.pid(),
             statistics.comm().c_str(),
-            BytesToKB(statistics.read()),
-            BytesToKB(statistics.write()),
-            BytesToKB(statistics.read_write()),
+            BytesToKB(statistics.read()) / delay_div,
+            BytesToKB(statistics.write()) / delay_div,
+            BytesToKB(statistics.read_write()) / delay_div,
             TimeToTgidPercent(statistics.delay_io(), delay, statistics),
             TimeToTgidPercent(statistics.delay_swap(), delay, statistics),
             TimeToTgidPercent(statistics.delay_sched(), delay, statistics),