--- a/src/hotspot/os/aix/os_perf_aix.cpp	Wed Apr 10 22:41:28 2019 -0400
+++ b/src/hotspot/os/aix/os_perf_aix.cpp	Wed Apr 10 09:33:32 2019 +0200
@@ -273,98 +273,12 @@
   return n;
 }
 
-static FILE* open_statfile(void) {
-  FILE *f;
-
-  if ((f = fopen("/proc/stat", "r")) == NULL) {
-    static int haveWarned = 0;
-    if (!haveWarned) {
-      haveWarned = 1;
-    }
-  }
-  return f;
-}
-
-static void
-next_line(FILE *f) {
-  int c;
-  do {
-    c = fgetc(f);
-  } while (c != '\n' && c != EOF);
-}
-
 /**
- * Return the total number of ticks since the system was booted.
- * If the usedTicks parameter is not NULL, it will be filled with
- * the number of ticks spent on actual processes (user, system or
- * nice processes) since system boot. Note that this is the total number
- * of "executed" ticks on _all_ CPU:s, that is on a n-way system it is
- * n times the number of ticks that has passed in clock time.
- *
- * Returns a negative value if the reading of the ticks failed.
+ * on Linux we got the ticks related information from /proc/stat
+ * this does not work on AIX, libperfstat might be an alternative
  */
 static OSReturn get_total_ticks(int which_logical_cpu, CPUPerfTicks* pticks) {
-  FILE*         fh;
-  uint64_t      userTicks, niceTicks, systemTicks, idleTicks;
-  uint64_t      iowTicks = 0, irqTicks = 0, sirqTicks= 0;
-  int           logical_cpu = -1;
-  const int     expected_assign_count = (-1 == which_logical_cpu) ? 4 : 5;
-  int           n;
-
-  if ((fh = open_statfile()) == NULL) {
-    return OS_ERR;
-  }
-  if (-1 == which_logical_cpu) {
-    n = fscanf(fh, "cpu " UINT64_FORMAT " " UINT64_FORMAT " " UINT64_FORMAT " "
-            UINT64_FORMAT " " UINT64_FORMAT " " UINT64_FORMAT " " UINT64_FORMAT,
-            &userTicks, &niceTicks, &systemTicks, &idleTicks,
-            &iowTicks, &irqTicks, &sirqTicks);
-  } else {
-    // Move to next line
-    next_line(fh);
-
-    // find the line for requested cpu faster to just iterate linefeeds?
-    for (int i = 0; i < which_logical_cpu; i++) {
-      next_line(fh);
-    }
-
-    n = fscanf(fh, "cpu%u " UINT64_FORMAT " " UINT64_FORMAT " " UINT64_FORMAT " "
-               UINT64_FORMAT " " UINT64_FORMAT " " UINT64_FORMAT " " UINT64_FORMAT,
-               &logical_cpu, &userTicks, &niceTicks,
-               &systemTicks, &idleTicks, &iowTicks, &irqTicks, &sirqTicks);
-  }
-
-  fclose(fh);
-  if (n < expected_assign_count || logical_cpu != which_logical_cpu) {
-    return OS_ERR;
-  }
-  pticks->used       = userTicks + niceTicks;
-  pticks->usedKernel = systemTicks + irqTicks + sirqTicks;
-  pticks->total      = userTicks + niceTicks + systemTicks + idleTicks +
-                       iowTicks + irqTicks + sirqTicks;
-
-  return OS_OK;
-}
-
-
-static int get_systemtype(void) {
-  static int procEntriesType = UNDETECTED;
-  DIR *taskDir;
-
-  if (procEntriesType != UNDETECTED) {
-    return procEntriesType;
-  }
-
-  // Check whether we have a task subdirectory
-  if ((taskDir = opendir("/proc/self/task")) == NULL) {
-    procEntriesType = UNDETECTABLE;
-  } else {
-    // The task subdirectory exists; we're on a Linux >= 2.6 system
-    closedir(taskDir);
-    procEntriesType = LINUX26_NPTL;
-  }
-
-  return procEntriesType;
+  return OS_ERR;
 }
 
 /** read user and system ticks from a named procfile, assumed to be in 'stat' format then. */
@@ -378,26 +292,7 @@
  * to the JVM on any CPU.
  */
 static OSReturn get_jvm_ticks(CPUPerfTicks* pticks) {
-  uint64_t userTicks;
-  uint64_t systemTicks;
-
-  if (get_systemtype() != LINUX26_NPTL) {
-    return OS_ERR;
-  }
-
-  if (read_ticks("/proc/self/stat", &userTicks, &systemTicks) != 2) {
-    return OS_ERR;
-  }
-
-  // get the total
-  if (get_total_ticks(-1, pticks) != OS_OK) {
-    return OS_ERR;
-  }
-
-  pticks->used       = userTicks;
-  pticks->usedKernel = systemTicks;
-
-  return OS_OK;
+  return OS_ERR;
 }
 
 /**
@@ -461,29 +356,7 @@
 }
 
 static int SCANF_ARGS(1, 2) parse_stat(_SCANFMT_ const char* fmt, ...) {
-  FILE *f;
-  va_list args;
-
-  va_start(args, fmt);
-
-  if ((f = open_statfile()) == NULL) {
-    va_end(args);
-    return OS_ERR;
-  }
-  for (;;) {
-    char line[80];
-    if (fgets(line, sizeof(line), f) != NULL) {
-      if (vsscanf(line, fmt, args) == 1) {
-        fclose(f);
-        va_end(args);
-        return OS_OK;
-      }
-    } else {
-        fclose(f);
-        va_end(args);
-        return OS_ERR;
-    }
-  }
+  return OS_ERR;
 }
 
 static int get_noof_context_switches(uint64_t* switches) {