From: Jens Axboe <axboe@kernel.dk>
Date: Wed, 14 Mar 2012 09:25:44 +0000 (+0100)
Subject: gfio: graphing updates
X-Git-Tag: gfio-0.1~155
X-Git-Url: https://git.kernel.dk/?p=fio.git;a=commitdiff_plain;h=d8fbeefb67641e9f63088b329de78a26a69fdbae;hp=a217ba7de6e2ea26fbd12db663aaf8a5a9f350a7

gfio: graphing updates

- Don't draw tickmark labels for an empty graph
- Remove Y-axis label. It was a bit awkward and hard to read.
- Ensure that we always put proper units on the Y-axis graph.
- Ensure that we always include the top most Y-axis tickmark
  and make that the ceiling, not the highest Y value. It's hard
  to visually understand a graph that is drawing somewhere above
  the last labeled tickmark.
- Fix rounding errors in graph.c

Signed-off-by: Jens Axboe <axboe@kernel.dk>
---

diff --git a/gfio.c b/gfio.c
index d0418a45..fc220f5d 100644
--- a/gfio.c
+++ b/gfio.c
@@ -187,70 +187,36 @@ static void gfio_update_thread_status(struct gui_entry *ge, char *status_message
 static void gfio_update_thread_status_all(char *status_message, double perc);
 void report_error(GError *error);
 
-static void iops_graph_y_axis_unit_change(struct graph *g, int power_of_ten)
-{
-	switch (power_of_ten) {
-		case 9: graph_y_title(g, "Billions of IOs / sec");
-			break;
-		case 6: graph_y_title(g, "Millions of IOs / sec");
-			break;
-		case 3: graph_y_title(g, "Thousands of IOs / sec");
-			break;
-		case 0:
-		default: graph_y_title(g, "IOs / sec");
-			break;
-	}
-}
-
 static struct graph *setup_iops_graph(void)
 {
 	struct graph *g;
 
 	g = graph_new(DRAWING_AREA_XDIM / 2.0, DRAWING_AREA_YDIM, gfio_graph_font);
-	graph_title(g, "IOPS");
+	graph_title(g, "IOPS (IOs/sec)");
 	graph_x_title(g, "Time (secs)");
-	graph_y_title(g, "IOs / sec");
 	graph_add_label(g, "Read IOPS");
 	graph_add_label(g, "Write IOPS");
 	graph_set_color(g, "Read IOPS", 0.13, 0.54, 0.13);
 	graph_set_color(g, "Write IOPS", 1.0, 0.0, 0.0);
 	line_graph_set_data_count_limit(g, gfio_graph_limit);
-	graph_y_axis_unit_change_notify(g, iops_graph_y_axis_unit_change);
-	graph_add_extra_space(g, 0.005, 0.005, 0.03, 0.03);
+	graph_add_extra_space(g, 0.0, 0.0, 0.0, 0.0);
 	return g;
 }
 
-static void bandwidth_graph_y_axis_unit_change(struct graph *g, int power_of_ten)
-{
-	switch (power_of_ten) {
-		case 9: graph_y_title(g, "Petabytes / sec");
-			break;
-		case 6: graph_y_title(g, "Gigabytes / sec");
-			break;
-		case 3: graph_y_title(g, "Megabytes / sec");
-			break;
-		case 0:
-		default: graph_y_title(g, "Kilobytes / sec");
-			break;
-	}
-}
-
 static struct graph *setup_bandwidth_graph(void)
 {
 	struct graph *g;
 
 	g = graph_new(DRAWING_AREA_XDIM / 2.0, DRAWING_AREA_YDIM, gfio_graph_font);
-	graph_title(g, "Bandwidth");
+	graph_title(g, "Bandwidth (bytes/sec)");
 	graph_x_title(g, "Time (secs)");
-	graph_y_title(g, "Kbytes / sec");
 	graph_add_label(g, "Read Bandwidth");
 	graph_add_label(g, "Write Bandwidth");
 	graph_set_color(g, "Read Bandwidth", 0.13, 0.54, 0.13);
 	graph_set_color(g, "Write Bandwidth", 1.0, 0.0, 0.0);
+	graph_set_base_offset(g, 1);
 	line_graph_set_data_count_limit(g, 100);
-	graph_y_axis_unit_change_notify(g, bandwidth_graph_y_axis_unit_change);
-	graph_add_extra_space(g, 0.005, 0.005, 0.03, 0.03);
-
+	graph_add_extra_space(g, 0.0, 0.0, 0.0, 0.0);
 	return g;
 }
 
diff --git a/graph.c b/graph.c
index aba095ba..5bcefbe4 100644
--- a/graph.c
+++ b/graph.c
@@ -66,6 +66,7 @@ struct graph {
 	const char *font;
 	graph_axis_unit_change_callback x_axis_unit_change_callback;
 	graph_axis_unit_change_callback y_axis_unit_change_callback;
+	unsigned int base_offset;
 	double left_extra;	
 	double right_extra;	
 	double top_extra;	
@@ -326,7 +327,7 @@ static void graph_draw_common(struct graph *g, cairo_t *cr,
 
 static void graph_draw_x_ticks(struct graph *g, cairo_t *cr,
 	double x1, double y1, double x2, double y2,
-	double minx, double maxx, int nticks)
+	double minx, double maxx, int nticks, int add_tm_text)
 {
 	struct tickmark *tm;
 	double tx;
@@ -334,13 +335,15 @@ static void graph_draw_x_ticks(struct graph *g, cairo_t *cr,
 	static double dash[] = { 1.0, 2.0 };
 
 	nticks = calc_tickmarks(minx, maxx, nticks, &tm, &power_of_ten,
-		g->x_axis_unit_change_callback == NULL);
+		g->x_axis_unit_change_callback == NULL, g->base_offset);
 	if (g->x_axis_unit_change_callback)
 		g->x_axis_unit_change_callback(g, power_of_ten);
 
 	for (i = 0; i < nticks; i++) {
 		tx = (((tm[i].value) - minx) / (maxx - minx)) * (x2 - x1) + x1;
-		if (tx < x1 || tx > x2)
+
+		/* really tx < yx || tx > x2, but protect against rounding */
+		if (x1 - tx > 0.01 || tx - x2 > 0.01)
 			continue;
 
 		/* Draw tick mark */
@@ -358,6 +361,9 @@ static void graph_draw_x_ticks(struct graph *g, cairo_t *cr,
 		cairo_stroke(cr);
 		cairo_restore(cr);
 
+		if (!add_tm_text)
+			continue;
+
 		/* draw tickmark label */
 		draw_centered_text(g, cr, tx, y2 * 1.04, 12.0, tm[i].string);
 		cairo_stroke(cr);
@@ -365,9 +371,9 @@ static void graph_draw_x_ticks(struct graph *g, cairo_t *cr,
 	}
 }
 
-static void graph_draw_y_ticks(struct graph *g, cairo_t *cr,
+static double graph_draw_y_ticks(struct graph *g, cairo_t *cr,
 	double x1, double y1, double x2, double y2,
-	double miny, double maxy, int nticks)
+	double miny, double maxy, int nticks, int add_tm_text)
 {
 	struct tickmark *tm;
 	double ty;
@@ -375,14 +381,24 @@ static void graph_draw_y_ticks(struct graph *g, cairo_t *cr,
 	static double dash[] = { 2.0, 2.0 };
 
 	nticks = calc_tickmarks(miny, maxy, nticks, &tm, &power_of_ten,
-		g->y_axis_unit_change_callback == NULL);
+		g->y_axis_unit_change_callback == NULL, g->base_offset);
 	if (g->y_axis_unit_change_callback)
 		g->y_axis_unit_change_callback(g, power_of_ten);
 
+	/*
+	 * Use highest tickmark as top of graph, not highest value. Otherwise
+	 * it's impossible to see what the max value is, if the graph is
+	 * fairly flat.
+	 */
+	maxy = tm[nticks - 1].value;
+
 	for (i = 0; i < nticks; i++) {
 		ty = y2 - (((tm[i].value) - miny) / (maxy - miny)) * (y2 - y1);
-		if (ty < y1 || ty > y2)
+
+		/* really ty < y1 || ty > y2, but protect against rounding */
+		if (y1 - ty > 0.01 || ty - y2 > 0.01)
 			continue;
+
 		/* draw tick mark */
 		cairo_move_to(cr, x1, ty);
 		cairo_line_to(cr, x1 - (x2 - x1) * 0.02, ty);
@@ -397,10 +413,18 @@ static void graph_draw_y_ticks(struct graph *g, cairo_t *cr,
 		cairo_stroke(cr);
 		cairo_restore(cr);
 
+		if (!add_tm_text)
+			continue;
+
 		/* draw tickmark label */
 		draw_right_justified_text(g, cr, x1 - (x2 - x1) * 0.025, ty, 12.0, tm[i].string);
 		cairo_stroke(cr);
 	}
+
+	/*
+	 * Return new max to use
+	 */
+	return maxy;
 }
 
 void bar_graph_draw(struct graph *bg, cairo_t *cr)
@@ -416,7 +440,7 @@ void bar_graph_draw(struct graph *bg, cairo_t *cr)
 	graph_draw_common(bg, cr, &x1, &y1, &x2, &y2);
 
 	nlabels = count_labels(bg->labels);
-	space_per_label = (x2 - x1) / (double) nlabels; 
+	space_per_label = (x2 - x1) / (double) nlabels;
 
 	mindata = find_min_data(bg->labels);
 	maxdata = find_max_data(bg->labels);
@@ -428,7 +452,7 @@ void bar_graph_draw(struct graph *bg, cairo_t *cr)
 		return;
 	}
 
-	graph_draw_y_ticks(bg, cr, x1, y1, x2, y2, mindata, maxdata, 10);
+	graph_draw_y_ticks(bg, cr, x1, y1, x2, y2, mindata, maxdata, 10, 1);
 
 	i = 0;
 	for (lb = bg->labels; lb; lb = lb->next) {
@@ -524,8 +548,8 @@ void line_graph_draw(struct graph *g, cairo_t *cr)
 	gminy = miny - bottom_extra;
 	gmaxy = maxy + top_extra;
 
-	graph_draw_x_ticks(g, cr, x1, y1, x2, y2, gminx, gmaxx, 10);
-	graph_draw_y_ticks(g, cr, x1, y1, x2, y2, gminy, gmaxy, 10);
+	graph_draw_x_ticks(g, cr, x1, y1, x2, y2, gminx, gmaxx, 10, good_data);
+	gmaxy = graph_draw_y_ticks(g, cr, x1, y1, x2, y2, gminy, gmaxy, 10, good_data);
 
 	if (!good_data)
 		goto skip_data;
@@ -776,6 +800,16 @@ void graph_add_extra_space(struct graph *g, double left_percent, double right_pe
 	g->bottom_extra = bottom_percent;	
 }
 
+/*
+ * Normally values are logged in a base unit of 0, but for other purposes
+ * it makes more sense to log in higher unit. For instance for bandwidth
+ * purposes, you may want to log in KB/sec (or MB/sec) rather than bytes/sec.
+ */
+void graph_set_base_offset(struct graph *g, unsigned int base_offset)
+{
+	g->base_offset = base_offset;
+}
+
 int graph_has_tooltips(struct graph *g)
 {
 	struct graph_label *i;
diff --git a/graph.h b/graph.h
index cb1e2d54..00995259 100644
--- a/graph.h
+++ b/graph.h
@@ -85,5 +85,7 @@ extern int graph_has_tooltips(struct graph *g);
 extern const char *graph_find_tooltip(struct graph *g, int x, int y);
 extern int graph_contains_xy(struct graph *p, int x, int y);
 
+extern void graph_set_base_offset(struct graph *g, unsigned int base_offset);
+
 #endif
 
diff --git a/tickmarks.c b/tickmarks.c
index 2605f721..6a964e31 100644
--- a/tickmarks.c
+++ b/tickmarks.c
@@ -40,11 +40,11 @@ static double nicenum(double x, int round)
 }
 
 static void shorten(struct tickmark *tm, int nticks, int *power_of_ten,
-			int use_KMG_symbols)
+			int use_KMG_symbols, int base_offset)
 {
-	int i, l, minshorten;
+	const char shorten_chr[] = { 0, 'K', 'M', 'G', 'P', 'E', 0 };
+	int i, l, minshorten, shorten_idx = 0;
 	char *str;
-	char shorten_char = '?';
 
 	minshorten = 100;
 	for (i = 0; i < nticks; i++) {
@@ -55,14 +55,14 @@ static void shorten(struct tickmark *tm, int nticks, int *power_of_ten,
 			continue;
 		if (l > 9 && strcmp(&str[l - 9], "000000000") == 0) {
 			*power_of_ten = 9;
-			shorten_char = use_KMG_symbols ? 'G' : '\0';
+			shorten_idx = 3;
 		} else if (6 < minshorten && l > 6 &&
 				strcmp(&str[l - 6], "000000") == 0) {
 			*power_of_ten = 6;
-			shorten_char = use_KMG_symbols ? 'M' : '\0';
+			shorten_idx = 2;
 		} else if (l > 3 && strcmp(&str[l - 3], "000") == 0) {
 			*power_of_ten = 3;
-			shorten_char = use_KMG_symbols ? 'K': '\0';
+			shorten_idx = 1;
 		} else {
 			*power_of_ten = 0;
 		}
@@ -73,17 +73,22 @@ static void shorten(struct tickmark *tm, int nticks, int *power_of_ten,
 
 	if (minshorten == 0)
 		return;
+	if (!use_KMG_symbols)
+		shorten_idx = 0;
+	else if (base_offset)
+		shorten_idx += base_offset;
 
 	for (i = 0; i < nticks; i++) {
 		str = tm[i].string;
 		l = strlen(str);
-		str[l - minshorten] = shorten_char;
-		str[l - minshorten + 1] = '\0';
+		str[l - minshorten] = shorten_chr[shorten_idx];
+		if (shorten_idx)
+			str[l - minshorten + 1] = '\0';
 	}
 }
 
 int calc_tickmarks(double min, double max, int nticks, struct tickmark **tm,
-		int *power_of_ten, int use_KMG_symbols)
+		int *power_of_ten, int use_KMG_symbols, int base_offset)
 {
 	char str[100];
 	int nfrac;
@@ -109,7 +114,7 @@ int calc_tickmarks(double min, double max, int nticks, struct tickmark **tm,
 		sprintf((*tm)[i].string, str, x);
 		i++;
 	}
-	shorten(*tm, i, power_of_ten, use_KMG_symbols);
+	shorten(*tm, i, power_of_ten, use_KMG_symbols, base_offset);
 	return i;
 }
 
diff --git a/tickmarks.h b/tickmarks.h
index a8c1bf9f..1e310dbb 100644
--- a/tickmarks.h
+++ b/tickmarks.h
@@ -7,6 +7,6 @@ struct tickmark {
 };
 
 int calc_tickmarks(double min, double max, int nticks, struct tickmark **tm,
-			int *power_of_ten, int use_KMG_symbols);
+			int *power_of_ten, int use_KMG_symbols, int base_off);
 
 #endif