r23531: added optional latency reporting in BENCH-NBENCH. To use it, you need

to have a load file that puts a timestamp in the first column. That
tells NBENCH to target the same throughput as the capture, and to
report the maximum amount of latency miss in the test

This allows you to quickly see how many clients you can run with while
still meeting a given target
(This used to be commit 7f045ca4f5e3e777978cad39ac22f0c611af6b10)

1 files changed, 33 insertions, 3 deletions

diff --git a/source4/torture/nbench/nbio.c b/source4/torture/nbench/nbio.c
index 26ea6520f6..a382c92ceb 100644
--- a/source4/torture/nbench/nbio.c
+++ b/source4/torture/nbench/nbio.c
@@ -53,8 +53,25 @@ static struct {
 	double bytes, warmup_bytes;
 	int line;
 	int done;
+	double max_latency;
+	struct timeval starttime;
 } *children;
 
+void nbio_time_reset(void)
+{
+	children[nbio_id].starttime = timeval_current();	
+}
+
+void nbio_time_delay(double targett)
+{
+	double elapsed = timeval_elapsed(&children[nbio_id].starttime);
+	if (targett > elapsed) {
+		msleep(1000*(targett - elapsed));
+	} else if (elapsed - targett > children[nbio_id].max_latency) {
+		children[nbio_id].max_latency = elapsed - targett;
+	}
+}
+
 double nbio_result(void)
 {
 	int i;
@@ -65,6 +82,19 @@ double nbio_result(void)
 	return 1.0e-6 * total / timeval_elapsed2(&tv_start, &tv_end);
 }
 
+double nbio_latency(void)
+{
+	int i;
+	double max_latency = 0;
+	for (i=0;i<nprocs;i++) {
+		if (children[i].max_latency > max_latency) {
+			max_latency = children[i].max_latency;
+			children[i].max_latency = 0;
+		}
+	}
+	return max_latency;
+}
+
 BOOL nb_tick(void)
 {
 	return children[nbio_id].done;
@@ -122,9 +152,9 @@ void nb_alarm(int sig)
 		       nprocs, lines/nprocs, 
 		       nbio_result(), t);
 	} else {
-		printf("%4d  %8d  %.2f MB/sec  execute %.0f sec   \n", 
+		printf("%4d  %8d  %.2f MB/sec  execute %.0f sec  latency %.2f msec \n", 
 		       nprocs, lines/nprocs, 
-		       nbio_result(), t);
+		       nbio_result(), t, nbio_latency() * 1.0e3);
 	}
 
 	fflush(stdout);
@@ -443,7 +473,7 @@ void nb_readx(int handle, off_t offset, int size, int ret_size, NTSTATUS status)
 	io.readx.in.remaining = 0;
 	io.readx.in.read_for_execute = False;
 	io.readx.out.data     = buf;
-		
+	
 	ret = smb_raw_read(c->tree, &io);
 
 	free(buf);