diff --git a/modules/libcom/src/osi/os/posix/osdThread.c b/modules/libcom/src/osi/os/posix/osdThread.c
index d2c548052..572cff198 100644
--- a/modules/libcom/src/osi/os/posix/osdThread.c
+++ b/modules/libcom/src/osi/os/posix/osdThread.c
@@ -1024,13 +1024,21 @@ LIBCOM_API void epicsStdCall *epicsThreadPrivateGet(epicsThreadPrivateId id)
 
 LIBCOM_API double epicsStdCall epicsThreadSleepQuantum ()
 {
-#ifdef CLOCK_REALTIME
-    struct timespec res;
-    if (clock_getres(CLOCK_REALTIME, &res) == 0)
-        return res.tv_sec + 1e-9 * res.tv_nsec;
-    else
+    double hz;
+#ifndef CLOCK_MONOTONIC_COARSE
+#ifdef CLOCK_MONOTONIC
+#define CLOCK_MONOTONIC_COARSE CLOCK_MONOTONIC
+#else
+#define CLOCK_MONOTONIC_COARSE CLOCK_REALTIME
 #endif
-    return 1e-3;
+#endif
+    struct timespec res;
+    if (clock_getres(CLOCK_MONOTONIC_COARSE, &res) == 0)
+        return res.tv_sec + 1e-9 * res.tv_nsec;
+    hz = sysconf ( _SC_CLK_TCK );
+    if(hz<=0)
+        return 0.0;
+    return 1.0 / hz;
 }
 
 LIBCOM_API int epicsThreadGetCPUs(void)