Added std dev

CHANGELOG.md

@@ -1,5 +1,9 @@
 # CHANGELOG
 
+### 1.2.0 - 2018-03-29
+
+Changed results display and added standard deviation for latency.
+
 ### 1.1.1 - 2018-02-25
 
 Fixed segfault on exit.

src/drop.c

@@ -156,14 +156,25 @@ drop_recv(Drop d, Pool p, bool enough) {
 	}
 	if (d->xsize <= d->rcnt) {
 	    double	dt = dtime() - d->pipeline[d->phead];
-
+	    double	ave;
+	    double	dif;
+
 	    p->ok_cnt++;
 	    d->pipeline[d->phead] = 0.0;
 	    d->phead++;
 	    if (PIPELINE_SIZE <= d->phead) {
 		d->phead = 0;
 	    }
 	    p->lat_sum += dt;
+	    ave = p->lat_sum / (double)p->ok_cnt;
+	    dif = dt - ave;
+	    p->lat_sq_sum += dif * dif;
+
+
+	    // TBD sum of (diff from on going average) squared
+	    // sq_sum
+
+
 	    /* TBD debugging, uses something better than a simple average for latency analysis.
 	       if (0.01 < dt && p->lat_sum * 2.0 / p->ok_cnt < dt) {
 	       printf("*** long latency: %0.3f msecs\n", dt * 1000.0);
@@ -173,7 +184,7 @@ drop_recv(Drop d, Pool p, bool enough) {
 		d->buf[d->xsize] = '\0';
 		printf("%s\n", d->buf);
 	    }
-	    if (enough || !d->h->keep_alive) {
+	    if ((enough || !d->h->keep_alive) && 0 >= drop_pending(d) ) {
 		drop_cleanup(d);
 		return true;
 	    } else {

src/drop.h

@@ -21,7 +21,7 @@ typedef struct _Drop {
     double		pipeline[PIPELINE_SIZE];
     int			phead;
     int			ptail;
-
+    
     long		rcnt;    // recv count
     long		xsize;   // expected size of message
     char		buf[MAX_RESP_SIZE];

src/perfer.c

@@ -2,6 +2,7 @@
 
 #include <errno.h>
 #include <inttypes.h>
+#include <math.h>
 #include <signal.h>
 #include <stdio.h>
 #include <stdlib.h>
@@ -17,7 +18,7 @@
 extern int asprintf(char **strp, const char *fmt, ...);
 #endif
 
-#define VERSION	"1.1.1"
+#define VERSION	"1.2.0"
 
 static struct _Perfer	perfer = {
     .inited = false,
@@ -304,7 +305,10 @@ perfer_init(Perfer h, int argc, const char **argv) {
     int		i;
     int		err;
     long	n = num / h->tcnt;
-
+
+    if (!h->keep_alive) {
+	h->backlog = 1;
+    }
     for (p = h->pools, i = h->tcnt; 0 < i; i--, p++) {
 	if (0 != (err = pool_init(p, h, n))) {
 	    return err;
@@ -354,6 +358,7 @@ perfer_start(Perfer h) {
     double	psum = 0.0;
     double	lat = 0.0;
     double	rate = 0.0;
+    double	stdev = 0.0;
 
     for (p = h->pools, i = h->tcnt; 0 < i; i--, p++) {
 	if (0 != (err = pool_start(p))) {
@@ -368,6 +373,7 @@ perfer_start(Perfer h) {
 	err_cnt += p->err_cnt;
 	lat_sum += p->lat_sum;
 	psum += p->actual_end - h->start_time;
+	stdev += p->lat_sq_sum;
     }
     // TBD actual times for each thread
     if (0 < err_cnt) {
@@ -381,11 +387,19 @@ perfer_start(Perfer h) {
     }
     if (0 < ok_cnt) {
 	lat = lat_sum * 1000.0 / ok_cnt;
+	stdev /= (double)ok_cnt;
+	stdev = sqrt(stdev) * 1000.0;
     }
-    printf("%s processed %ld requests in %0.3f seconds for a rate of %ld Requests/sec.\n",
-	   h->addr, ok_cnt, psum / h->tcnt, (long)rate);
-    printf("with an average latency of %0.3f msecs\n", lat);
-
+    printf("Benchmarks for:\n");
+    printf("  URL:                %s/%s\n", h->addr, h->path);
+    printf("  Threads:            %ld\n", h->tcnt);
+    printf("  Connections/thread: %ld\n", h->ccnt);
+    printf("  Duration:           %0.1f seconds\n", psum / h->tcnt);
+    printf("  Keep-Alive:         %s\n", h->keep_alive ? "true" : "false");
+    printf("Results:\n");
+    printf("  Throughput:         %ld requests/second\n", (long)rate);
+    printf("  Latency:            %0.3f +/-%0.3f msecs (and stdev)\n", lat, stdev);
+
     return 0;
 }
 

src/pool.c

@@ -28,6 +28,7 @@ pool_init(Pool p, struct _Perfer *h, long num) {
     p->err_cnt = 0;
     p->ok_cnt = 0;
     p->lat_sum = 0.0;
+    p->lat_sq_sum = 0.0;
     p->actual_end = 0.0;
     if (NULL == (p->drops = (Drop)malloc(sizeof(struct _Drop) * p->dcnt))) {
 	printf("-*-*- Failed to allocate %d connections.\n", p->dcnt);

src/pool.h

@@ -17,6 +17,7 @@ typedef struct _Pool {
     long		err_cnt;
     long		ok_cnt;
     double		lat_sum;
+    double		lat_sq_sum;
     double		actual_end;
     struct _Perfer	*perfer;
     pthread_t		thread;