diff --git a/core/experiments/coolchecksum/campaign.cc b/core/experiments/coolchecksum/campaign.cc
index fa2d0779..a8ac5e10 100644
--- a/core/experiments/coolchecksum/campaign.cc
+++ b/core/experiments/coolchecksum/campaign.cc
@@ -4,6 +4,7 @@
 #include "experimentInfo.hpp"
 #include "controller/CampaignManager.hpp"
 #include "util/Logger.hpp"
+#include "util/ProtoStream.hpp"
 #include "SAL/SALConfig.hpp"
 
 #if COOL_FAULTSPACE_PRUNING
@@ -82,9 +83,7 @@ bool CoolChecksumCampaign::run()
 		log << "couldn't open " << trace_filename << endl;
 		return false;
 	}
-	Trace trace;
-	trace.ParseFromIstream(&tracef);
-	tracef.close();
+	ProtoIStream ps(&tracef);
 
 	// set of equivalence classes that need one (rather: eight, one for
 	// each bit in that byte) experiment to determine them all
@@ -105,19 +104,19 @@ bool CoolChecksumCampaign::run()
 		// XXX reorganizing the trace for efficient seeks could speed this up
 		int instr = 0;
 		sal::address_t instr_absolute = 0; // FIXME this one probably should also be recorded ...
-		Trace_Event const *ev;
-		for (int eventnr = 0; eventnr < trace.event_size(); ++eventnr) {
-			ev = &trace.event(eventnr);
-
+		Trace_Event ev;
+		ps.reset();
+		
+		while(ps.getNext(&ev)) {
 			// only count instruction events
-			if (!ev->has_memaddr()) {
+			if (!ev.has_memaddr()) {
 				// new instruction
 				instr++;
-				instr_absolute = ev->ip();
+				instr_absolute = ev.ip();
 				continue;
 
 			// skip accesses to other data
-			} else if (ev->memaddr() != byte_offset + COOL_ECC_OBJUNDERTEST) {
+			} else if (ev.memaddr() != byte_offset + COOL_ECC_OBJUNDERTEST) {
 				continue;
 
 			// skip zero-sized intervals: these can
@@ -137,12 +136,12 @@ bool CoolChecksumCampaign::run()
 			current_ec.instr2_absolute = instr_absolute;
 			current_ec.byte_offset = byte_offset;
 
-			if (ev->accesstype() == ev->READ) {
+			if (ev.accesstype() == ev.READ) {
 				// a sequence ending with READ: we need
 				// to do one experiment to cover it
 				// completely
 				ecs_need_experiment.push_back(current_ec);
-			} else if (ev->accesstype() == ev->WRITE) {
+			} else if (ev.accesstype() == ev.WRITE) {
 				// a sequence ending with WRITE: an
 				// injection anywhere here would have
 				// no effect.
diff --git a/core/experiments/coolchecksum/experiment.cc b/core/experiments/coolchecksum/experiment.cc
index 62d063f4..70719973 100644
--- a/core/experiments/coolchecksum/experiment.cc
+++ b/core/experiments/coolchecksum/experiment.cc
@@ -62,8 +62,8 @@ bool CoolChecksumExperiment::run()
 	tp.restrictMemoryAddresses(&mm);
 
 	// record trace
-	Trace trace;
-	tp.setTraceMessage(&trace);
+	std::ofstream of("trace.pb");
+	tp.setTraceFile(&of);
 
 	// this must be done *after* configuring the plugin:
 	sal::simulator.addFlow(&tp);
@@ -86,13 +86,11 @@ bool CoolChecksumExperiment::run()
 	sal::simulator.removeFlow(&tp);
 
 	// serialize trace to file
-	std::ofstream of("trace.pb");
 	if (of.fail()) {
 		log << "failed to write trace.pb" << endl;
 		sal::simulator.clearEvents(this);
 		return false;
 	}
-	trace.SerializeToOstream(&of);
 	of.close();
 #endif
 
diff --git a/core/plugins/tracing/TracingPlugin.cc b/core/plugins/tracing/TracingPlugin.cc
index eff96fa8..961bbe60 100644
--- a/core/plugins/tracing/TracingPlugin.cc
+++ b/core/plugins/tracing/TracingPlugin.cc
@@ -22,7 +22,10 @@ bool TracingPlugin::run()
 	if (m_memonly || !m_iponly) {
 		simulator.addEvent(&ev_mem);
 	}
-
+	if(m_protoStreamFile) {
+		ps = new ProtoOStream(m_protoStreamFile);
+	}
+	
 	while (true) {
 		ev = simulator.waitAny();
 
@@ -36,9 +39,10 @@ bool TracingPlugin::run()
 
 			if (m_os)
 				*m_os << "[Tracing] IP " << hex << ip << "\n";
-			if (m_trace) {
-				Trace_Event *e = m_trace->add_event();
-				e->set_ip(ip);
+			if (m_protoStreamFile) {
+				Trace_Event e;
+				e.set_ip(ip);
+				ps->writeMessage(&e);
 			}
 		} else if (ev == &ev_mem) {
 			simulator.addEvent(&ev_mem);
@@ -56,14 +60,15 @@ bool TracingPlugin::run()
 				      << ((ev_mem.getTriggerAccessType() &
 				           MemAccessEvent::MEM_READ) ? "R " : "W ")
 				      << addr << " width " << width << " IP " << ip << "\n";
-			if (m_trace) {
-				Trace_Event *e = m_trace->add_event();
-				e->set_ip(ip);
-				e->set_memaddr(addr);
-				e->set_width(width);
-				e->set_accesstype(
+			if (m_protoStreamFile) {
+				Trace_Event e;
+				e.set_ip(ip);
+				e.set_memaddr(addr);
+				e.set_width(width);
+				e.set_accesstype(
 				  (ev_mem.getTriggerAccessType() & MemAccessEvent::MEM_READ) ?
-				  e->READ : e->WRITE);
+				  e.READ : e.WRITE);
+				ps->writeMessage(&e);
 			}
 		} else {
 			if (m_os)
diff --git a/core/plugins/tracing/TracingPlugin.hpp b/core/plugins/tracing/TracingPlugin.hpp
index 8ca4f9f9..6f1d108d 100644
--- a/core/plugins/tracing/TracingPlugin.hpp
+++ b/core/plugins/tracing/TracingPlugin.hpp
@@ -4,6 +4,7 @@
 #include <ostream>
 #include "controller/ExperimentFlow.hpp"
 #include "util/MemoryMap.hpp"
+#include "util/ProtoStream.hpp"
 #include "config/FailConfig.hpp"
 
 #include "plugins/tracing/trace.pb.h"
@@ -41,13 +42,14 @@ private:
 	bool m_memonly; //!< log instructions only if they are memory accesses
 	bool m_iponly; //!< log instruction addresses only
 
-	Trace *m_trace; //!< protobuf message to store trace in
+	std::ostream *m_protoStreamFile;
 	std::ostream *m_os; //!< ostream to write human-readable trace into
+	ProtoOStream *ps;
 
 public:
 	TracingPlugin()
 	 : m_memMap(0), m_ipMap(0), m_memonly(false), m_iponly(false),
-	   m_trace(0), m_os(0) { }
+	   m_protoStreamFile(0), m_os(0) { }
 	bool run();
 	/**
 	 * Restricts tracing to memory addresses listed in this MemoryMap.  An
@@ -77,9 +79,9 @@ public:
 	 */
 	void setOstream(std::ostream *os) { m_os = os; }
 	/**
-	 * Protobuf message to trace into (trace.proto instance)
+	 * ProtoStream file to trace into (trace.proto instance)
 	 */
-	void setTraceMessage(Trace *trace) { m_trace = trace; }
+	void setTraceFile(std::ostream *os) { m_protoStreamFile = os; }
 };
 
 #endif /* __TRACING_PLUGIN_HPP__ */
diff --git a/core/plugins/tracing/trace.proto b/core/plugins/tracing/trace.proto
index ce91207d..ee3589e8 100644
--- a/core/plugins/tracing/trace.proto
+++ b/core/plugins/tracing/trace.proto
@@ -1,6 +1,5 @@
-message Trace {
-  repeated group Event = 1{
-    required uint64 ip = 1;
+message Trace_Event {
+	required uint64 ip = 1;
     optional uint64 memaddr = 2;
     optional uint32 width = 3;
     enum AccessType {
@@ -8,5 +7,4 @@ message Trace {
       WRITE = 2;
     }
     optional AccessType accesstype = 4;
-  }
 }
diff --git a/core/util/CMakeLists.txt b/core/util/CMakeLists.txt
index a655bd13..f79d9732 100644
--- a/core/util/CMakeLists.txt
+++ b/core/util/CMakeLists.txt
@@ -2,6 +2,7 @@ set(SRCS
 	SynchronizedCounter.cc
 	Logger.hpp
 	Logger.cc
+	ProtoStream.cc
 )
 
 add_library(util ${SRCS})