Latency measurement tool

This commit is contained in:
Quentin Dufour 2019-02-20 16:50:44 +01:00
parent cb075c8ea1
commit c5dfffe08d
2 changed files with 139 additions and 7 deletions

View file

@ -1,23 +1,121 @@
#include <stdlib.h>
#include <stdio.h>
#include <sys/timerfd.h>
#include <time.h>
#include <unistd.h>
#include "evt_core.h"
#include "net_tools.h"
struct timer_ctx {
struct measure_conf {
int udp_fd;
uint64_t max_measure;
uint64_t payload_size;
char* payload;
uint64_t counter;
};
struct packet_header {
uint64_t counter;
struct timespec emit_time;
};
struct measure_conf* create_measure_conf(int udp_sock, char* max_mes, char* plsize) {
struct measure_conf* mc = malloc(sizeof(struct measure_conf));
if (mc == NULL) {
perror("Malloc failed");
exit(EXIT_FAILURE);
}
if (udp_sock >= 0) {
mc->udp_fd = dup(udp_sock);
if (mc->udp_fd == -1) {
perror("Dup failed");
exit(EXIT_FAILURE);
}
}
mc->counter = 0;
mc->max_measure = atoi(max_mes);
mc->payload_size = atoi(plsize);
mc->payload = malloc(mc->payload_size);
if (mc->payload == NULL) {
perror("malloc failed");
exit(EXIT_FAILURE);
}
return mc;
}
void on_udp(struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinfo) {
ssize_t res;
int secs, nsecs;
uint64_t micro_sec;
struct timespec curr;
struct measure_conf* mc = fdinfo->other;
res = read(fdinfo->fd, mc->payload, mc->payload_size);
if (res != mc->payload_size) {
perror("read error");
exit(EXIT_FAILURE);
}
struct packet_header* head = (struct packet_header*) mc->payload;
if (clock_gettime(CLOCK_MONOTONIC, &curr) == -1){
perror("clock_gettime error");
exit(EXIT_FAILURE);
}
secs = curr.tv_sec - head->emit_time.tv_sec;
nsecs = curr.tv_nsec - head->emit_time.tv_nsec;
micro_sec = secs * 1000000 + nsecs / 1000;
printf("Packet %llu latency %luµs\n", (unsigned long long)head->counter, micro_sec);
if (head->counter >= mc->max_measure) {
printf("Measurement done\n");
exit(EXIT_SUCCESS);
}
}
void on_timer(struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinfo) {
ssize_t s;
uint64_t ticks;
struct measure_conf* mc = fdinfo->other;
s = read(fdinfo->fd, &ticks, sizeof(uint64_t));
if (s != sizeof(uint64_t)) {
perror("Read error");
exit(EXIT_FAILURE);
}
if (ticks != 1) {
fprintf(stderr, "Has ticked %lu times, expected 1 time. This is a bug\n", ticks);
}
mc->counter += ticks;
memset(mc->payload, 0, mc->payload_size);
struct packet_header* head = (struct packet_header*)mc->payload;
head->counter = mc->counter;
if (clock_gettime(CLOCK_MONOTONIC, &head->emit_time) == -1) {
perror("clock_gettime error");
exit(EXIT_FAILURE);
}
s = send(mc->udp_fd, mc->payload, mc->payload_size, 0);
if (s < 0) {
perror("Send error");
exit(EXIT_FAILURE);
}
}
void free_timer_conf(void* v) {
struct measure_conf* mc = v;
close(mc->udp_fd);
free(mc->payload);
free(mc);
}
int main(int argc, char** argv) {
printf("~ measlat ~\n");
if (argc < 3) exit(EXIT_FAILURE);
if (argc < 6){
fprintf(stderr, "%s host port interval count payload-size\n", argv[0]);
exit(EXIT_FAILURE);
}
struct timer_ctx apptime = {0};
struct evt_core_ctx evts = {0};
struct evt_core_cat udp_read = {
.app_ctx = NULL,
@ -29,7 +127,7 @@ int main(int argc, char** argv) {
.socklist = NULL
};
struct evt_core_cat timer = {
.app_ctx = &apptime,
.app_ctx = NULL,
.free_app_ctx = NULL,
.cb = on_timer,
.err_cb = NULL,
@ -52,8 +150,42 @@ int main(int argc, char** argv) {
fdinfo.fd = udp_sock;
fdinfo.cat->name = "udp-read";
fdinfo.other = create_measure_conf (-1, argv[4], argv[5]);
sprintf(fdinfo.url, "udp:read:%s:%s", argv[1], argv[2]);
evt_core_add_fd (&evts, &fdinfo);
printf("--- UDP socket registered\n");
struct timespec now;
struct itimerspec timer_config;
if (clock_gettime(CLOCK_REALTIME, &now) == -1) {
perror("clock_gettime");
return 1;
}
uint64_t micro_sec = atoi(argv[3]);
timer_config.it_value.tv_sec = now.tv_sec + 1;
timer_config.it_value.tv_nsec = now.tv_nsec;
timer_config.it_interval.tv_sec = micro_sec / 1000;
timer_config.it_interval.tv_nsec = micro_sec % 1000 * 1000000;
fdinfo.fd = timerfd_create(CLOCK_REALTIME, 0);
if (fdinfo.fd == -1) {
perror("Unable to timerfd_create");
return 1;
}
if (timerfd_settime (fdinfo.fd, TFD_TIMER_ABSTIME, &timer_config, NULL) == -1) {
perror("Unable to timerfd_time");
return 1;
}
fdinfo.cat->name = "timer";
fdinfo.other = create_measure_conf(udp_sock, argv[4], argv[5]);
fdinfo.free_other = free_timer_conf;
sprintf(fdinfo.url, "timer:%s:%s", argv[3], argv[4]);
evt_core_add_fd (&evts, &fdinfo);
printf("--- Timer registered\n");
evt_core_loop(&evts);
return 0;
}

View file

@ -25,10 +25,10 @@ def receive_next(sock):
def receive_and_send_one(sock):
"Waits for a single datagram over the socket and echoes it back."
input_data, addr = receive_next(sock)
message = input_data.decode()
logger.info("Received message from %s: %s (%s bytes).", addr, message, len(input_data))
#message = input_data.decode()
#logger.info("Received message from %s: %s (%s bytes).", addr, message, len(input_data))
output_len = sock.sendto(input_data, addr)
logger.info("Echoed message back to %s: %s (%s bytes).", addr, message, output_len)
#logger.info("Echoed message back to %s: %s (%s bytes).", addr, message, output_len)
def start(args):
"Runs the server."