diff --git a/src/mem/ruby/system/PersistentTable.cc b/src/mem/ruby/system/PersistentTable.cc
new file mode 100644
index 000000000..1e056f6e5
--- /dev/null
+++ b/src/mem/ruby/system/PersistentTable.cc
@@ -0,0 +1,190 @@
+
+/*
+ * Copyright (c) 1999-2008 Mark D. Hill and David A. Wood
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met: redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer;
+ * redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution;
+ * neither the name of the copyright holders nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "PersistentTable.hh"
+#include "NetDest.h"
+#include "Map.h"
+#include "Address.h"
+#include "AbstractChip.h"
+#include "util.h"
+
+// randomize so that handoffs are not locality-aware
+// int persistent_randomize[] = {0, 4, 8, 12, 1, 5, 9, 13, 2, 6, 10, 14, 3, 7, 11, 15};
+// int persistent_randomize[] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15};
+
+
+class PersistentTableEntry {
+public:
+  NetDest m_starving;
+  NetDest m_marked;
+  NetDest m_request_to_write;
+};
+
+PersistentTable::PersistentTable(AbstractChip* chip_ptr, int version)
+{
+  m_chip_ptr = chip_ptr;
+  m_map_ptr = new Map<Address, PersistentTableEntry>;
+  m_version = version;
+}
+
+PersistentTable::~PersistentTable()
+{
+  delete m_map_ptr;
+  m_map_ptr = NULL;
+  m_chip_ptr = NULL;
+}  
+
+void PersistentTable::persistentRequestLock(const Address& address, MachineID locker, AccessType type)
+{
+
+  // if (locker == m_chip_ptr->getID()  )
+  // cout << "Chip " << m_chip_ptr->getID() << ": " << llocker << " requesting lock for " << address << endl;
+
+  // MachineID locker = (MachineID) persistent_randomize[llocker];
+ 
+  assert(address == line_address(address));
+  if (!m_map_ptr->exist(address)) {
+    // Allocate if not present
+    PersistentTableEntry entry;
+    entry.m_starving.add(locker);
+    if (type == AccessType_Write) {
+      entry.m_request_to_write.add(locker);
+    }
+    m_map_ptr->add(address, entry);
+  } else {
+    PersistentTableEntry& entry = m_map_ptr->lookup(address);
+    assert(!(entry.m_starving.isElement(locker))); // Make sure we're not already in the locked set
+
+    entry.m_starving.add(locker);
+    if (type == AccessType_Write) {
+      entry.m_request_to_write.add(locker);
+    }
+    assert(entry.m_marked.isSubset(entry.m_starving));
+  }
+}
+
+void PersistentTable::persistentRequestUnlock(const Address& address, MachineID unlocker)
+{
+  // if (unlocker == m_chip_ptr->getID() )
+  // cout << "Chip " << m_chip_ptr->getID() << ": " << uunlocker << " requesting unlock for " << address << endl;
+
+  // MachineID unlocker = (MachineID) persistent_randomize[uunlocker];
+
+  assert(address == line_address(address));
+  assert(m_map_ptr->exist(address));
+  PersistentTableEntry& entry = m_map_ptr->lookup(address);
+  assert(entry.m_starving.isElement(unlocker)); // Make sure we're in the locked set
+  assert(entry.m_marked.isSubset(entry.m_starving));
+  entry.m_starving.remove(unlocker);
+  entry.m_marked.remove(unlocker);
+  entry.m_request_to_write.remove(unlocker);
+  assert(entry.m_marked.isSubset(entry.m_starving));
+
+  // Deallocate if empty
+  if (entry.m_starving.isEmpty()) {
+    assert(entry.m_marked.isEmpty());
+    m_map_ptr->erase(address);
+  }
+}
+
+bool PersistentTable::okToIssueStarving(const Address& address) const
+{
+  assert(address == line_address(address));
+  if (!m_map_ptr->exist(address)) {
+    return true; // No entry present
+  } else if (m_map_ptr->lookup(address).m_starving.isElement( (MachineID) {MachineType_L1Cache, m_version})) {
+    return false; // We can't issue another lockdown until are previous unlock has occurred
+  } else {
+    return (m_map_ptr->lookup(address).m_marked.isEmpty());
+  }
+}
+
+MachineID PersistentTable::findSmallest(const Address& address) const
+{
+  assert(address == line_address(address));
+  assert(m_map_ptr->exist(address));
+  const PersistentTableEntry& entry = m_map_ptr->lookup(address);
+  // cout << "Node " <<  m_chip_ptr->getID() << " returning " << persistent_randomize[entry.m_starving.smallestElement()] << " for findSmallest(" << address << ")" << endl;
+  // return (MachineID) persistent_randomize[entry.m_starving.smallestElement()];
+  return (MachineID) { MachineType_L1Cache, entry.m_starving.smallestElement() };
+}
+
+AccessType PersistentTable::typeOfSmallest(const Address& address) const
+{
+  assert(address == line_address(address));
+  assert(m_map_ptr->exist(address));
+  const PersistentTableEntry& entry = m_map_ptr->lookup(address);
+  if (entry.m_request_to_write.isElement((MachineID) {MachineType_L1Cache, entry.m_starving.smallestElement()})) {
+    return AccessType_Write;
+  } else {
+    return AccessType_Read;
+  }
+}
+
+void PersistentTable::markEntries(const Address& address)
+{
+  assert(address == line_address(address));
+  if (m_map_ptr->exist(address)) {
+    PersistentTableEntry& entry = m_map_ptr->lookup(address);
+    assert(entry.m_marked.isEmpty());  // None should be marked
+    entry.m_marked = entry.m_starving; // Mark all the nodes currently in the table
+  }
+}
+
+bool PersistentTable::isLocked(const Address& address) const
+{
+  assert(address == line_address(address));
+  // If an entry is present, it must be locked
+  return (m_map_ptr->exist(address));
+}
+
+int PersistentTable::countStarvingForAddress(const Address& address) const
+{
+  if (m_map_ptr->exist(address)) {
+    PersistentTableEntry& entry = m_map_ptr->lookup(address);
+    return (entry.m_starving.count());
+  }
+  else {
+    return 0;
+  }
+}
+
+int PersistentTable::countReadStarvingForAddress(const Address& address) const
+{
+  int count = 0;
+  if (m_map_ptr->exist(address)) {
+    PersistentTableEntry& entry = m_map_ptr->lookup(address);
+    return (entry.m_starving.count() - entry.m_request_to_write.count());
+  }
+  else {
+    return 0;
+  }
+}
+
+
diff --git a/src/mem/ruby/system/PersistentTable.hh b/src/mem/ruby/system/PersistentTable.hh
new file mode 100644
index 000000000..ab000843d
--- /dev/null
+++ b/src/mem/ruby/system/PersistentTable.hh
@@ -0,0 +1,92 @@
+
+/*
+ * Copyright (c) 1999-2008 Mark D. Hill and David A. Wood
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met: redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer;
+ * redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution;
+ * neither the name of the copyright holders nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef PersistentTable_H
+#define PersistentTable_H
+
+#include "Global.h"
+#include "MachineID.h"
+#include "AccessType.h"
+
+class AbstractChip;
+
+template <class KEY_TYPE, class VALUE_TYPE> class Map;
+class Address;
+class PersistentTableEntry;
+
+class PersistentTable {
+public:
+  // Constructors
+  PersistentTable(AbstractChip* chip_ptr, int version);
+
+  // Destructor
+  ~PersistentTable();
+  
+  // Public Methods
+  void persistentRequestLock(const Address& address, MachineID locker, AccessType type);
+  void persistentRequestUnlock(const Address& address, MachineID unlocker);
+  bool okToIssueStarving(const Address& address) const;
+  MachineID findSmallest(const Address& address) const;
+  AccessType typeOfSmallest(const Address& address) const;
+  void markEntries(const Address& address);
+  bool isLocked(const Address& addr) const;
+  int countStarvingForAddress(const Address& addr) const;
+  int countReadStarvingForAddress(const Address& addr) const;
+
+  static void printConfig(ostream& out) {}
+
+  void print(ostream& out) const;
+private:
+  // Private Methods
+
+  // Private copy constructor and assignment operator
+  PersistentTable(const PersistentTable& obj);
+  PersistentTable& operator=(const PersistentTable& obj);
+
+  // Data Members (m_prefix)
+  Map<Address, PersistentTableEntry>* m_map_ptr;
+  AbstractChip* m_chip_ptr;
+  int m_version;
+};
+
+// Output operator declaration
+ostream& operator<<(ostream& out, const PersistentTable& obj);
+
+// ******************* Definitions *******************
+
+// Output operator definition
+extern inline 
+ostream& operator<<(ostream& out, const PersistentTable& obj)
+{
+  obj.print(out);
+  out << flush;
+  return out;
+}
+
+#endif //PersistentTable_H