diff --git a/core/gate_hooks/tcpdump.cc b/core/gate_hooks/tcpdump.cc
index c58a71017..fb01ccf10 100644
--- a/core/gate_hooks/tcpdump.cc
+++ b/core/gate_hooks/tcpdump.cc
@@ -83,15 +83,17 @@ void Tcpdump::ProcessBatch(const bess::PacketBatch *batch) {
 
   for (int i = 0; i < batch->cnt(); i++) {
     bess::Packet *pkt = batch->pkts()[i];
+    size_t snaplen = std::min(pkt->head_len(), 2048);
+
     struct pcap_rec_hdr rec = {
         .ts_sec = (uint32_t)tv.tv_sec,
         .ts_usec = (uint32_t)tv.tv_usec,
-        .incl_len = (uint32_t)pkt->head_len(),
+        .incl_len = (uint32_t)snaplen,
         .orig_len = (uint32_t)pkt->total_len(),
     };
 
     struct iovec vec[2] = {{&rec, sizeof(rec)},
-                           {pkt->head_data(), (size_t)pkt->head_len()}};
+                           {pkt->head_data(), snaplen}};
 
     int ret = writev(fd, vec, 2);
     if (ret < 0) {
diff --git a/core/modules/flowgen.h b/core/modules/flowgen.h
index 990e3b869..e2833d303 100644
--- a/core/modules/flowgen.h
+++ b/core/modules/flowgen.h
@@ -40,7 +40,7 @@
 #include "../utils/endian.h"
 #include "../utils/random.h"
 
-#define MAX_TEMPLATE_SIZE 1536
+#define MAX_TEMPLATE_SIZE (SNBUF_DATA - 512)
 
 typedef std::pair<uint64_t, struct flow *> Event;
 typedef std::priority_queue<Event, std::vector<Event>, std::greater<Event>>
diff --git a/core/modules/rewrite.h b/core/modules/rewrite.h
index d0a154d91..1aad7c8a5 100644
--- a/core/modules/rewrite.h
+++ b/core/modules/rewrite.h
@@ -37,7 +37,7 @@
 class Rewrite final : public Module {
  public:
   static const size_t kNumSlots = bess::PacketBatch::kMaxBurst * 2 - 1;
-  static const size_t kMaxTemplateSize = 1536;
+  static const size_t kMaxTemplateSize = (SNBUF_DATA - 512);
 
   static const Commands cmds;
 
diff --git a/core/snbuf_layout.h b/core/snbuf_layout.h
index 598e406ba..f8431a42b 100644
--- a/core/snbuf_layout.h
+++ b/core/snbuf_layout.h
@@ -56,7 +56,7 @@
 #define SNBUF_SCRATCHPAD 64
 #define SNBUF_RESERVE (SNBUF_IMMUTABLE + SNBUF_METADATA + SNBUF_SCRATCHPAD)
 #define SNBUF_HEADROOM 128
-#define SNBUF_DATA 2048
+#define SNBUF_DATA (12 * 1024 - 512) // total: 12K (HEADROOM + DATA)
 
 #define SNBUF_MBUF_OFF 0
 #define SNBUF_IMMUTABLE_OFF SNBUF_MBUF