diff --git a/examples/attachtest.cpp b/examples/attachtest.cpp
index 018d32ef4..03ee928b4 100644
--- a/examples/attachtest.cpp
+++ b/examples/attachtest.cpp
@@ -16,17 +16,6 @@ int main (void)
     time_t start, end;
     double time_diff;
     DFHack::API DF("Memory.xml");
-    //if(!DF.Attach())
-    //{
-    //    cerr << "DF not found" << endl;
-    //    return 1;
-    //}
-    //if(!DF.Detach())
-    //{
-    //    cerr << "Can't detach from DF" << endl;
-    //    return 1;
-    //}
-    
     try
     {
         DF.Attach();
@@ -77,11 +66,11 @@ int main (void)
     cout << "Testing suspend/resume"  << endl;
     DF.Attach();
     time(&start);
-    for (int i = 0; i < 1000000; i++)
+    for (int i = 0; i < 1000; i++)
     {
         DF.Suspend();
-        if(i%10000 == 0)
-            cout << i / 10000 << "%" << endl;
+        if(i%10 == 0)
+            cout << i / 10 << "%" << endl;
         DF.Resume();
     }
     time(&end);
diff --git a/examples/expbench.cpp b/examples/expbench.cpp
index 7f083e49b..ba2606749 100644
--- a/examples/expbench.cpp
+++ b/examples/expbench.cpp
@@ -29,15 +29,15 @@ int main (void)
     }
     
     time(&start);
-    for(uint32_t i = 0; i< 1000;i++)
+    for(uint32_t i = 0; i< 10000;i++)
     {
         if(!DF.InitMap())
             break;
         DF.getSize(x_max,y_max,z_max);
-        if((i % 10) == 0)
+        if((i % 100) == 0)
         {
-            int percentage = i / 10;
-            cout << percentage << endl;
+            int percentage = i / 100;
+            cout << percentage << " %" << endl;
         }
         for(uint32_t x = 0; x< x_max;x++)
         {
diff --git a/library/DFProcess-linux-SHM.cpp b/library/DFProcess-linux-SHM.cpp
index e31ce062f..9bcda4ff2 100644
--- a/library/DFProcess-linux-SHM.cpp
+++ b/library/DFProcess-linux-SHM.cpp
@@ -30,6 +30,8 @@ distribution.
 #include "../shmserver/shms.h"
 #include <sys/time.h>
 #include <time.h>
+#include <sched.h>
+
 using namespace DFHack;
 
 // a full memory barrier! better be safe than sorry.
@@ -74,6 +76,7 @@ bool SHMProcess::Private::waitWhile (DF_PINGPONG state)
     {
         if(cnt == 10000)
         {
+            
             shmctl(my_shmid, IPC_STAT, &descriptor); 
             if(descriptor.shm_nattch == 1)// DF crashed?
             {
@@ -87,6 +90,7 @@ bool SHMProcess::Private::waitWhile (DF_PINGPONG state)
                 cnt = 0;
             }
         }
+        SCHED_YIELD
         cnt++;
     }
     if(((shm_cmd *)my_shm)->pingpong == DFPP_SV_ERROR)
@@ -254,10 +258,6 @@ SHMProcess::~SHMProcess()
     {
         delete d->my_window;
     }
-    if(d->my_shm)
-    {
-        fprintf(stderr,"detach: %d",shmdt(d->my_shm));
-    }
     delete d;
 }
 
@@ -411,6 +411,7 @@ bool SHMProcess::detach()
     {
         d->attached = false;
         d->suspended = false;
+        d->my_shm = 0;
         g_pProcess = 0;
         return true;
     }
diff --git a/precompiled/linux/libdfconnect.so b/precompiled/linux/libdfconnect.so
index 9d90a8d34..6db5d6d3b 100755
Binary files a/precompiled/linux/libdfconnect.so and b/precompiled/linux/libdfconnect.so differ
diff --git a/shmserver/shms.h b/shmserver/shms.h
index 6da1322cb..c23225971 100644
--- a/shmserver/shms.h
+++ b/shmserver/shms.h
@@ -12,7 +12,9 @@
 #ifdef LINUX_BUILD
     // a full memory barrier! better be safe than sorry.
     #define full_barrier asm volatile("" ::: "memory"); __sync_synchronize();
-    #define SCHED_YIELD
+    #define SCHED_YIELD sched_yield(); // slow but allows the SHM to work on single-core
+    // #define SCHED_YIELD usleep(0); // extremely slow
+    // #define SCHED_YIELD // works only on multi-core
 #else
     // we need windows.h for Sleep()
     #define _WIN32_WINNT 0x0501 // needed for INPUT struct