added timers

This commit is contained in:
Steffen Vogel 2015-07-20 16:08:04 +02:00
parent 8bb1700ffd
commit 5e30762904
2 changed files with 93 additions and 18 deletions

View file

@ -5,10 +5,19 @@
* @license GPLv3
*********************************************************************************/
#define _POSIX_C_SOURCE 200809L
#include <stdio.h>
#include <errno.h>
#include <error.h>
#include <time.h>
#include <netlink/route/qdisc/netem.h>
#include <netlink/route/tc.h>
#include "tc.h"
#include "config.h"
#include "timing.h"
int emulate(int argc, char *argv[])
{
@ -25,8 +34,8 @@ int emulate(int argc, char *argv[])
struct rtnl_tc *cls_fw = NULL;
struct tc_netem netem = {
.delay = 1000000,
.limit = cfg.limit
.limit = cfg.limit,
.delay = 100000
};
/* Create connection to netlink */
@ -48,24 +57,60 @@ int emulate(int argc, char *argv[])
if (ret)
error(-1, 0, "Failed to setup TC: prio qdisc: %s", nl_geterror(ret));
ret = tc_netem(sock, link, &qdisc_netem, &netem);
if (ret)
error(-1, 0, "Failed to setup TC: netem qdisc: %s", nl_geterror(ret));
ret = tc_classifier(sock, link, &cls_fw, cfg.mark, cfg.mask);
if (ret)
error(-1, 0, "Failed to setup TC: fw filter: %s", nl_geterror(ret));
int run = 0;
while (cfg.limit && run < cfg.limit) {
rtnl_tc_dump_stats(qdisc_netem, &dp_param);
sleep(1);
ret = tc_netem(sock, link, &qdisc_netem, &netem);
if (ret)
error(-1, 0, "Failed to setup TC: netem qdisc: %s", nl_geterror(ret));
/* We will use the default normal distribution for now */
rtnl_netem_set_delay_distribution(qdisc_netem, "normal");
/* Start timer */
struct itimerspec its = {
.it_interval = time_from_double(1 / cfg.rate),
.it_value = { 1, 0 }
};
int tfd = timerfd_create(CLOCK_REALTIME, 0);
if (tfd < 0)
error(-1, errno, "Failed to create timer");
if (timerfd_settime(tfd, 0, &its, NULL))
error(-1, errno, "Failed to start timer");
char *line = NULL;
size_t linelen = 0;
unsigned run = 0;
while (!cfg.limit || run < cfg.limit) {
float rtt, mu, sigma;
netem.delay += 10000;
/* Show queuing discipline statistics */
rtnl_tc_dump_stats(qdisc_netem, &dp_param);
/* Parse new data */
if (feof(stdin) || getline(&line, &linelen, stdin) == -1)
error(-1, errno, "Failed to read data from stdin");
if (line[0] == '#')
continue;
if (sscanf(line, "%f %f %f ", &rtt, &mu, &sigma) != 3)
error(-1, 0, "Invalid data format");
/* Update the netem config according to the measurements */
/* TODO: Add more characteristics */
netem.delay = (mu / 2) * 1e6;
netem.jitter = sigma * 1e6;
ret = tc_netem(sock, link, &qdisc_netem, &netem);
if (ret)
error(-1, 0, "Failed to update TC: netem qdisc: %s", nl_geterror(ret));
timerfd_wait(tfd);
run++;
}

44
probe.c
View file

@ -20,6 +20,7 @@
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/poll.h>
#include <sys/timerfd.h>
#include <netinet/in.h>
#include <net/if.h>
@ -148,25 +149,54 @@ int probe(int argc, char *argv[])
struct hist hist;
hist_create(&hist, 0, 0, 1);
while (hist.total < cfg.limit) {
probe_tcp(sd, &ts);
/* Start timer */
struct itimerspec its = {
.it_interval = time_from_double(1 / cfg.rate),
.it_value = { 1, 0 }
};
int tfd = timerfd_create(CLOCK_REALTIME, 0);
if (tfd < 0)
error(-1, errno, "Failed to create timer");
if (timerfd_settime(tfd, 0, &its, NULL))
error(-1, errno, "Failed to start timer");
unsigned run = 0;
while (cfg.limit && run < cfg.limit) {
probe_tcp(sd, dport, &ts);
double rtt = time_to_double(&ts);
hist_put(&hist, rtt);
printf("n=%u, rtt=%f, min=%f, max=%f, avg=%f, stddev=%f\n",
hist.total, rtt, hist.lowest, hist.highest, hist_mean(&hist), hist_stddev(&hist));
//printf("n=%u, rtt=%f, min=%f, max=%f, avg=%f, stddev=%f\n",
// hist.total, rtt, hist.lowest, hist.highest, hist_mean(&hist), hist_stddev(&hist));
/* Warmup: adjust histogram after rough estimation of RTT */
if (hist.total == 20 && hist.high == 0) {
if (run == 20) {
double span = hist.highest - hist.lowest;
hist_destroy(&hist);
hist_create(&hist, MAX(0, hist.lowest - span * 0.1), hist.highest + span * 0.2, 1e-3);
hist_create(&hist, MAX(0, hist.lowest - span * 0.1), hist.highest + span * 0.2, span / 20);
printf("Created new histogram: high=%f, low=%f, buckets=%u\n",
hist.high, hist.low, hist.length);
/* Print header for output */
time_t t = time(NULL);
struct tm *tm = localtime(&t);
char addrs[32], date[32];
nl_addr2str(addr, addrs, sizeof(addrs));
strftime(date, sizeof(date), "%a, %d %b %Y %T %z", tm);
printf("# Probing: %s on port %u\n", addrs, dport);
printf("# Started: %s\n", date);
printf("# RTT mu sigma (units in S)\n");
}
//else if (run > 20)
printf("%f %f %f\n", rtt, hist_mean(&hist), hist_stddev(&hist));
//usleep(250 * 1e3); // 250 ms
timerfd_wait(tfd);
run++;
}
hist_print(&hist);