diff --git a/lci/runtime/1sided_primitive.c b/lci/runtime/1sided_primitive.c
index c286ca83..49db3933 100644
--- a/lci/runtime/1sided_primitive.c
+++ b/lci/runtime/1sided_primitive.c
@@ -49,7 +49,8 @@ LCI_error_t LCI_putmac(LCI_endpoint_t ep, LCI_mbuffer_t buffer, int rank,
                  "(set by LCI_plist_set_default_comp, "
                  "the default value is LCI_UR_CQ)\n");
   LCI_error_t ret = LCI_OK;
-  bool is_user_provided_packet = LCII_is_packet(buffer.address);
+  bool is_user_provided_packet =
+      LCII_is_packet(ep->device->heap, buffer.address);
   if (local_completion == NULL && buffer.length <= LCI_SHORT_SIZE) {
     /* if data is this short, we will be able to inline it
      * no reason to get a packet, allocate a ctx, etc */
diff --git a/lci/runtime/2sided_primitive.c b/lci/runtime/2sided_primitive.c
index 0d77586a..4b063854 100644
--- a/lci/runtime/2sided_primitive.c
+++ b/lci/runtime/2sided_primitive.c
@@ -26,7 +26,8 @@ LCI_error_t LCI_sendmc(LCI_endpoint_t ep, LCI_mbuffer_t buffer, int rank,
                  "buffer is too large %lu (maximum: %d)\n", buffer.length,
                  LCI_MEDIUM_SIZE);
   LCI_error_t ret = LCI_OK;
-  bool is_user_provided_packet = LCII_is_packet(buffer.address);
+  bool is_user_provided_packet =
+      LCII_is_packet(ep->device->heap, buffer.address);
   if (completion == NULL && buffer.length <= LCI_SHORT_SIZE) {
     /* if data is this short, we will be able to inline it
      * no reason to get a packet, allocate a ctx, etc */
diff --git a/lci/runtime/device.c b/lci/runtime/device.c
index ceea1f94..b3f41593 100644
--- a/lci/runtime/device.c
+++ b/lci/runtime/device.c
@@ -60,7 +60,9 @@ LCI_error_t LCI_device_init(LCI_device_t* device_ptr)
   LCII_bq_init(&device->bq);
   LCIU_spinlock_init(&device->bq_spinlock);
 
-  LCI_memory_register(device, g_heap, g_heap_size, &device->heap_segment);
+  device->heap = &g_heap;
+  LCI_memory_register(device, device->heap->address, device->heap->length,
+                      &device->heap_segment);
 
   if (LCI_ENABLE_PRG_NET_ENDPOINT)
     LCII_fill_rq(device->endpoint_progress, true);
@@ -80,10 +82,10 @@ LCI_error_t LCI_device_free(LCI_device_t* device_ptr)
   LCI_device_t device = *device_ptr;
   LCI_Log(LCI_LOG_INFO, "device", "free device %p\n", device);
   LCI_barrier();
-  g_total_recv_posted +=
+  device->heap->total_recv_posted +=
       LCII_endpoint_get_recv_posted(device->endpoint_worker);
   if (LCI_ENABLE_PRG_NET_ENDPOINT) {
-    g_total_recv_posted +=
+    device->heap->total_recv_posted +=
         LCII_endpoint_get_recv_posted(device->endpoint_progress);
   }
   LCII_matchtable_free(&device->mt);
diff --git a/lci/runtime/endpoint.c b/lci/runtime/endpoint.c
index 04f62c13..f70a0de9 100644
--- a/lci/runtime/endpoint.c
+++ b/lci/runtime/endpoint.c
@@ -14,7 +14,7 @@ LCI_error_t LCII_endpoint_init(LCI_endpoint_t* ep_ptr, LCI_device_t device,
   *ep_ptr = ep;
 
   ep->device = device;
-  ep->pkpool = g_pkpool;
+  ep->pkpool = device->heap->pool;
   ep->mt = device->mt;
   ep->ctx_archive_p = &device->ctx_archive;
   ep->bq_p = &device->bq;
diff --git a/lci/runtime/lci.c b/lci/runtime/lci.c
index 46f5c041..d69dc834 100644
--- a/lci/runtime/lci.c
+++ b/lci/runtime/lci.c
@@ -8,11 +8,47 @@ int LCIU_nthreads = 0;
 __thread int LCIU_thread_id = -1;
 __thread unsigned int LCIU_rand_seed = 0;
 LCIS_server_t g_server;
-void *g_heap;
-size_t g_heap_size;
-void *g_base_packet;
-LCII_pool_t* g_pkpool;
-int g_total_recv_posted;
+LCII_packet_heap_t g_heap;
+
+void initialize_packet_heap(LCII_packet_heap_t* heap)
+{
+  heap->length = LCI_CACHE_LINE + (size_t)LCI_SERVER_NUM_PKTS * LCI_PACKET_SIZE;
+  heap->address = LCIU_memalign(LCI_PAGESIZE, heap->length);
+  LCI_Assert(LCI_CACHE_LINE >= sizeof(struct LCII_packet_context),
+             "packet context is too large!\n");
+  heap->base_packet_p =
+      heap->address + LCI_CACHE_LINE - sizeof(struct LCII_packet_context);
+  LCI_Assert(LCI_PACKET_SIZE % LCI_CACHE_LINE == 0,
+             "The size of packets should be a multiple of cache line size\n");
+  LCII_pool_create(&heap->pool);
+  for (size_t i = 0; i < LCI_SERVER_NUM_PKTS; i++) {
+    LCII_packet_t* packet =
+        (LCII_packet_t*)(heap->base_packet_p + i * LCI_PACKET_SIZE);
+    LCI_Assert(((uint64_t) & (packet->data)) % LCI_CACHE_LINE == 0,
+               "packet.data is not well-aligned\n");
+    LCI_Assert(LCII_is_packet(heap, packet->data.address),
+               "Not a packet. The computation is wrong!\n");
+    packet->context.pkpool = heap->pool;
+    packet->context.poolid = 0;
+#ifdef LCI_DEBUG
+    packet->context.isInPool = true;
+#endif
+    LCII_pool_put(heap->pool, packet);
+  }
+  LCI_Assert(LCI_SERVER_NUM_PKTS > 2 * LCI_SERVER_MAX_RECVS,
+             "The packet number is too small!\n");
+  heap->total_recv_posted = 0;
+}
+
+void finalize_packet_heap(LCII_packet_heap_t* heap)
+{
+  int total_num = LCII_pool_count(heap->pool) + heap->total_recv_posted;
+  if (total_num != LCI_SERVER_NUM_PKTS)
+    LCI_Warn("Potentially losing packets %d != %d\n", total_num,
+             LCI_SERVER_NUM_PKTS);
+  LCII_pool_destroy(heap->pool);
+  LCIU_free(heap->address);
+}
 
 LCI_error_t LCI_initialize()
 {
@@ -43,34 +79,7 @@ LCI_error_t LCI_initialize()
   }
   // initialize global data structure
   LCIS_server_init(&g_server);
-  g_heap_size =
-      LCI_CACHE_LINE + (size_t)LCI_SERVER_NUM_PKTS * LCI_PACKET_SIZE;
-  g_heap = LCIU_memalign(LCI_PAGESIZE, g_heap_size);
-  LCI_Assert(LCI_CACHE_LINE >= sizeof(struct LCII_packet_context),
-             "packet context is too large!\n");
-  g_base_packet =
-      g_heap + LCI_CACHE_LINE - sizeof(struct LCII_packet_context);
-  LCI_Assert(LCI_PACKET_SIZE % LCI_CACHE_LINE == 0,
-             "The size of packets should be a multiple of cache line size\n");
-
-  LCII_pool_create(&g_pkpool);
-  for (size_t i = 0; i < LCI_SERVER_NUM_PKTS; i++) {
-    LCII_packet_t* packet =
-        (LCII_packet_t*)(g_base_packet + i * LCI_PACKET_SIZE);
-    LCI_Assert(((uint64_t) & (packet->data)) % LCI_CACHE_LINE == 0,
-               "packet.data is not well-aligned\n");
-    LCI_Assert(LCII_is_packet(packet->data.address),
-               "Not a packet. The computation is wrong!\n");
-    packet->context.pkpool = g_pkpool;
-    packet->context.poolid = 0;
-#ifdef LCI_DEBUG
-    packet->context.isInPool = true;
-#endif
-    LCII_pool_put(g_pkpool, packet);
-  }
-  LCI_Assert(LCI_SERVER_NUM_PKTS > 2 * LCI_SERVER_MAX_RECVS,
-             "The packet number is too small!\n");
-  g_total_recv_posted = 0;
+  initialize_packet_heap(&g_heap);
   // UR objects
   LCI_device_init(&LCI_UR_DEVICE);
   LCI_queue_create(LCI_UR_DEVICE, &LCI_UR_CQ);
@@ -101,13 +110,8 @@ LCI_error_t LCI_finalize()
   LCI_endpoint_free(&LCI_UR_ENDPOINT);
   LCI_queue_free(&LCI_UR_CQ);
   LCI_device_free(&LCI_UR_DEVICE);
-  int total_num = LCII_pool_count(g_pkpool) + g_total_recv_posted;
-  if (total_num != LCI_SERVER_NUM_PKTS)
-    LCI_Warn("Potentially losing packets %d != %d\n", total_num,
-             LCI_SERVER_NUM_PKTS);
-  LCII_pool_destroy(g_pkpool);
-  LCIU_free(g_heap);
   LCIS_server_fina(g_server);
+  finalize_packet_heap(&g_heap);
   if (LCI_USE_DREG) {
 #ifdef LCI_COMPILE_DREG
     LCII_ucs_cleanup();
diff --git a/lci/runtime/lcii.h b/lci/runtime/lcii.h
index 06cb2a5e..7b476a4c 100644
--- a/lci/runtime/lcii.h
+++ b/lci/runtime/lcii.h
@@ -58,22 +58,29 @@ struct LCII_endpoint_t {
 };
 typedef struct LCII_endpoint_t LCII_endpoint_t;
 
+struct LCII_packet_heap_t {
+  void* address;
+  size_t length;
+  void* base_packet_p;
+  LCII_pool_t* pool;
+  int total_recv_posted;  // for debugging purpose
+};
+typedef struct LCII_packet_heap_t LCII_packet_heap_t;
+
 extern LCIS_server_t g_server;
-extern void *g_heap;
-extern size_t g_heap_size;
-extern void *g_base_packet;
-extern LCII_pool_t* g_pkpool;
-extern int g_total_recv_posted;
+extern LCII_packet_heap_t g_heap;
 
 struct __attribute__((aligned(LCI_CACHE_LINE))) LCI_device_s {
   // the following will not be changed after initialization
   LCII_endpoint_t* endpoint_worker;    // 8B
   LCII_endpoint_t* endpoint_progress;  // 8B
   LCI_matchtable_t mt;                 // 8B
+  LCII_packet_heap_t* heap;            // 8B
   LCII_rcache_t rcache;                // 8B
   LCI_segment_t heap_segment;          // 8B
   LCIU_CACHE_PADDING(2 * sizeof(LCIS_endpoint_t) + sizeof(LCI_matchtable_t) +
-                     sizeof(LCII_rcache_t) + sizeof(LCI_segment_t));
+                     sizeof(LCII_packet_heap_t*) + sizeof(LCII_rcache_t) +
+                     sizeof(LCI_segment_t));
   // the following is shared by both progress threads and worker threads
   LCM_archive_t ctx_archive;  // used for long message protocol
   LCIU_CACHE_PADDING(sizeof(LCM_archive_t));
diff --git a/lci/runtime/memory_registration.c b/lci/runtime/memory_registration.c
index 602293ae..2335b6ad 100644
--- a/lci/runtime/memory_registration.c
+++ b/lci/runtime/memory_registration.c
@@ -33,7 +33,7 @@ LCI_error_t LCI_memory_deregister(LCI_segment_t* segment)
 
 LCI_error_t LCI_mbuffer_alloc(LCI_device_t device, LCI_mbuffer_t* mbuffer)
 {
-  LCII_packet_t* packet = LCII_alloc_packet_nb(g_pkpool);
+  LCII_packet_t* packet = LCII_alloc_packet_nb(device->heap->pool);
   if (packet == NULL)
     // no packet is available
     return LCI_ERR_RETRY;
@@ -41,7 +41,7 @@ LCI_error_t LCI_mbuffer_alloc(LCI_device_t device, LCI_mbuffer_t* mbuffer)
 
   mbuffer->address = packet->data.address;
   mbuffer->length = LCI_MEDIUM_SIZE;
-  LCI_DBG_Assert(LCII_is_packet(mbuffer->address), "");
+  LCI_DBG_Assert(LCII_is_packet(device->heap, mbuffer->address), "");
   return LCI_OK;
 }
 
diff --git a/lci/runtime/packet.h b/lci/runtime/packet.h
index 40e77858..f51abaf2 100644
--- a/lci/runtime/packet.h
+++ b/lci/runtime/packet.h
@@ -102,12 +102,12 @@ static inline LCII_packet_t* LCII_mbuffer2packet(LCI_mbuffer_t mbuffer)
   return (LCII_packet_t*)(mbuffer.address - offsetof(LCII_packet_t, data));
 }
 
-static inline bool LCII_is_packet(void* address)
+static inline bool LCII_is_packet(LCII_packet_heap_t* heap, void* address)
 {
   void* packet_address =
       (LCII_packet_t*)(address - offsetof(LCII_packet_t, data));
-  uintptr_t offset = (uintptr_t)packet_address - (uintptr_t)g_base_packet;
-  return (uintptr_t)packet_address >= (uintptr_t)g_base_packet &&
+  uintptr_t offset = (uintptr_t)packet_address - (uintptr_t)heap->base_packet_p;
+  return (uintptr_t)packet_address >= (uintptr_t)heap->base_packet_p &&
          offset % LCI_PACKET_SIZE == 0 &&
          offset / LCI_PACKET_SIZE < LCI_SERVER_NUM_PKTS;
 }
diff --git a/lci/runtime/progress.c b/lci/runtime/progress.c
index d3b89f2b..79b02b94 100644
--- a/lci/runtime/progress.c
+++ b/lci/runtime/progress.c
@@ -113,7 +113,7 @@ LCI_error_t LCII_fill_rq(LCII_endpoint_t* endpoint, bool block)
 
     // First, get a packet.
     LCII_PCOUNTER_START(get_recv_packet_timer);
-    LCII_packet_t* packet = LCII_alloc_packet_nb(g_pkpool);
+    LCII_packet_t* packet = LCII_alloc_packet_nb(endpoint->device->heap->pool);
     LCII_PCOUNTER_END(get_recv_packet_timer);
     if (packet == NULL) {
       LCII_PCOUNTER_ADD(net_recv_failed_nopacket, 1);