TASS Belgium / Mbed 2 deprecated Pico_MEM_Test

Picotcp memory usage benchmark (still beta testing)

Dependencies:   PicoTCP lpc1768-picotcp-eth mbed-rtos mbed

This project represents a throughtput test for the EthernetInterface, based on the PicoTCP library.

The purpose of this is to be able to make a comparison of full speed (Rx,Tx and Rx+Tx) and memory between the EthernetInterface based on the lwIP and the one based on PicoTCP .

The benchmark consists of three parts:

• we are sending 1 Megabyte from the board to host
• we are waiting for the host to send us 1 Megabyte of data
• on the last part we are using a TCP Echo Server to send and receive back 1 Megabyte of data

we send/receive 1024 packets of 1024 bytes each and we measure how many bits per second we transmit and receive.

The result:
TX+RX Throughput: 4194304 bytes in 3 seconds (10.457) Mbits/s

Memory report
Current free memory : 19148 bytes
Maximum free memory : 24716 bytes
Minimum free memory : 15476 bytes
Average free memory : 17376 bytes

The python script used

#!/usr/bin/python
import sys, socket
import random, string
import select
from time import time
#ECHO_SERVER_ADDRESS = "10.20.30.139"
ECHO_SERVER_ADDRESS = "192.168.100.12"
ECHO_SERVER_PORT = 7
N_PACKETS = 1024
LEN_PACKET = 1024

TOT_BITS = (LEN_PACKET * N_PACKETS * 8) * 4. # TX bits + RX bits
PACKET = ''.join(random.choice(string.ascii_uppercase+string.digits) for _ in range(LEN_PACKET))
MEGA = 1024 * 1024.
UPDATE_STEP = (N_PACKETS/20) # Make the update step such as one step = 5%
UPDATE_R_STEP = (N_PACKETS/20) #Make the update step such as one step = 1%
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.connect((ECHO_SERVER_ADDRESS, ECHO_SERVER_PORT))
start = time()
rx_total = 0
tx_total = 0
data = ''
i = 0
lp = []
p = select.poll()
while(True): # keeping this in for robustness testing, when the test will run for days
	#Stage I - sending data from host towards mbed board	
	print "Started sending data...."
	while (i < N_PACKETS):
	  p.register(s, select.POLLOUT)
	  lp = p.poll(1)
	  if (len(lp) > 0):
	    s.sendall(PACKET)
	    i+=1
	    if (i % UPDATE_STEP) == 0: print "sent %d/%d (%.2f%%)" % (i, N_PACKETS, float(i)/ float(N_PACKETS) * 100.)
	    continue

	#Stage II - receving data from the mbed board
	print "Started receiving data...."
	while(len(data) < N_PACKETS * LEN_PACKET):	
		p.register(s, select.POLLIN)
		lp = p.poll(1)
		if(len(lp) > 0):
		    r = s.recv(LEN_PACKET)
		    if (r != ''):
		      data += r
		      if (len(data) / LEN_PACKET) % UPDATE_R_STEP: print "recvd %d/%d (%.2f%%)" % (len(data)/LEN_PACKET, N_PACKETS, float(len(data))/ float(N_PACKETS * LEN_PACKET) * 100.)
		    else:
		      print "Error receiving !"
		      sys.exit(1)

	#Stage III - echo between host and mbed board
	print "Started echoing data...."
	for i in range(N_PACKETS):
		if (i % UPDATE_STEP) == 0: print "%.2f%%" % (float(i)/float(N_PACKETS) * 100.)
		s.sendall(PACKET)
		data = s.recv(LEN_PACKET)
		if (len(data) != LEN_PACKET):
			print "Error echoing !"
			sys.exit(1)

	print "Test was finished!"
	break;	

t = time() - start
s.close()
print "TX+RX Throughput: %d bytes in %d seconds (%.3f)Mbits/s" % (TOT_BITS / 8, t, ((TOT_BITS / t) / MEGA))

This test is based on the following libraries

Click here to see the results for lwIP

--- a/mbed-rtos.lib	Fri Sep 06 10:11:46 2013 +0000
+++ b/mbed-rtos.lib	Mon Oct 07 10:43:36 2013 +0000
@@ -1,1 +1,1 @@
-http://mbed.org/users/mbed_official/code/mbed-rtos/#869ef732a8a2
+http://mbed.org/users/mbed_official/code/mbed-rtos/#ee87e782d34f