[Write Amplification Factor]

src/host/IO_Flow_Base.cpp

@@ -36,7 +36,7 @@ IO_Flow_Base::IO_Flow_Base(const sim_object_id_type &name, uint16_t flow_id, LHA
 																												STAT_min_request_delay(MAXIMUM_TIME), STAT_min_request_delay_read(MAXIMUM_TIME), STAT_min_request_delay_write(MAXIMUM_TIME),
 																												STAT_max_request_delay(0), STAT_max_request_delay_read(0), STAT_max_request_delay_write(0),
 																												STAT_transferred_bytes_total(0), STAT_transferred_bytes_read(0), STAT_transferred_bytes_write(0), progress(0), next_progress_step(0),
-																												enabled_logging(enabled_logging), logging_period(logging_period), logging_file_path(logging_file_path)
+																												enabled_logging(enabled_logging), logging_period(logging_period), logging_file_path(logging_file_path), total_write_requests_to_be_generated(0)
 {
 	Host_IO_Request *t = NULL;
 
@@ -564,21 +564,34 @@ IO_Flow_Base::IO_Flow_Base(const sim_object_id_type &name, uint16_t flow_id, LHA
 		std::string val = ID();
 		xmlwriter.Write_attribute_string(attr, val);
 
-		attr = "Request_Count";
-		val = std::to_string(STAT_generated_request_count);
-		xmlwriter.Write_attribute_string(attr, val);
-
-		attr = "Read_Request_Count";
-		val = std::to_string(STAT_generated_read_request_count);
-		xmlwriter.Write_attribute_string(attr, val);
-
-		attr = "Write_Request_Count";
-		val = std::to_string(STAT_generated_write_request_count);
-		xmlwriter.Write_attribute_string(attr, val);
-
-		attr = "IOPS";
-		val = std::to_string((double)STAT_generated_request_count / (Simulator->Time() / SIM_TIME_TO_SECONDS_COEFF));
-		xmlwriter.Write_attribute_string(attr, val);
+        attr = "Request_Count";
+        val = std::to_string(STAT_generated_request_count);
+        xmlwriter.Write_attribute_string(attr, val);
+
+        attr = "Read_Request_Count";
+        val = std::to_string(STAT_generated_read_request_count);
+        xmlwriter.Write_attribute_string(attr, val);
+
+        attr = "Write_Request_Count";
+        val = std::to_string(STAT_generated_write_request_count);
+        xmlwriter.Write_attribute_string(attr, val);
+        attr = "Host_Write_Request_Count";
+        val = std::to_string(total_write_requests_to_be_generated);
+        xmlwriter.Write_attribute_string(attr, val);
+
+        attr = "Actual_Writes_on_Flash";
+        val = std::to_string(Simulator->stats->IssuedProgramCMD + Simulator->stats->IssuedMultiplaneProgramCMD);
+        xmlwriter.Write_attribute_string(attr, val);
+
+        attr = "Write_Amplification";
+        val = std::to_string(
+                (double) (Simulator->stats->IssuedProgramCMD + Simulator->stats->IssuedMultiplaneProgramCMD) /
+                total_write_requests_to_be_generated);
+
+        xmlwriter.Write_attribute_string(attr, val);
+        attr = "IOPS";
+        val = std::to_string((double) STAT_generated_request_count / (Simulator->Time() / SIM_TIME_TO_SECONDS_COEFF));
+        xmlwriter.Write_attribute_string(attr, val);
 
 		attr = "IOPS_Read";
 		val = std::to_string((double)STAT_generated_read_request_count / (Simulator->Time() / SIM_TIME_TO_SECONDS_COEFF));

src/host/IO_Flow_Base.h

@@ -73,6 +73,7 @@ namespace Host_Components
 		double initial_occupancy_ratio;//The initial amount of valid logical pages when pereconditioning is performed
 		sim_time_type stop_time;//The flow stops generating request when simulation time reaches stop_time
 		unsigned int total_requests_to_be_generated;//If stop_time is zero, then the flow stops generating request when the number of generated requests is equal to total_req_count
+        unsigned int total_write_requests_to_be_generated; // To Calculate Write Amplification we need to first see how many write requests are actually being made by the host
 		HostInterface_Types SSD_device_type;
 		PCIe_Root_Complex* pcie_root_complex;
 		SATA_HBA* sata_hba;

src/host/IO_Flow_Integration_Based.cpp

@@ -58,6 +58,7 @@ namespace Host_Components {
         if (user_data_req->type == kREQUEST_TYPE::WRITE) {
             request->Type = Host_IO_Request_Type::WRITE;
             STAT_generated_write_request_count++;
+            ++total_write_requests_to_be_generated;
         } else {
             request->Type = Host_IO_Request_Type::READ;
             STAT_generated_read_request_count++;

src/host/IO_Flow_Synthetic.cpp

@@ -88,6 +88,7 @@ IO_Flow_Synthetic::IO_Flow_Synthetic(const sim_object_id_type &name, uint16_t fl
 		} else {
 			request->Type = Host_IO_Request_Type::WRITE;
 			STAT_generated_write_request_count++;
+            ++total_write_requests_to_be_generated;
 		}
 
 		switch (request_size_distribution) {

src/host/IO_Flow_Trace_Based.cpp

@@ -140,6 +140,7 @@ void IO_Flow_Trace_Based::Start_simulation()
 	PRINT_MESSAGE("Investigating input trace file: " << trace_file_path);
 
 	sim_time_type last_request_arrival_time = 0;
+    auto total_write_requests_in_file = 0;
 	while (std::getline(trace_file, trace_line))
 	{
 		Utils::Helper_Functions::Remove_cr(trace_line);
@@ -150,6 +151,9 @@ void IO_Flow_Trace_Based::Start_simulation()
 			break;
 		}
 		total_requests_in_file++;
+        if (current_trace_line[ASCIITraceTypeColumn] == ASCIITraceWriteCode) {
+            ++total_write_requests_in_file;
+        }
 		sim_time_type prev_time = last_request_arrival_time;
 		last_request_arrival_time = std::strtoll(current_trace_line[ASCIITraceTimeColumn].c_str(), &pEnd, 10);
 		if (last_request_arrival_time < prev_time)
@@ -164,11 +168,13 @@ void IO_Flow_Trace_Based::Start_simulation()
 	if (total_replay_no == 1)
 	{
 		total_requests_to_be_generated = (int)(((double)percentage_to_be_simulated / 100) * total_requests_in_file);
-	}
+        total_write_requests_to_be_generated += (int)(((double)percentage_to_be_simulated / 100) * total_write_requests_in_file);
+    }
 	else
 	{
 		total_requests_to_be_generated = total_requests_in_file * total_replay_no;
-	}
+        total_write_requests_to_be_generated += (int)(((double)percentage_to_be_simulated / 100) * total_write_requests_in_file);
+    }
 
 	trace_file.open(trace_file_path);
 	current_trace_line.clear();