X-Git-Url: https://git.kernel.dk/?p=fio.git;a=blobdiff_plain;f=graph.c;h=837211dacebdb4f47defcc6e5b02ce9149c0b25c;hp=a0f1b056d696c6f979c9154c77e521812ea4c34a;hb=5aec66804d2a6d60aee8d973680c69b13c1d34a3;hpb=9ede9c9c00f5457564677833cc44d436b7c936c4

diff --git a/graph.c b/graph.c
index a0f1b056..837211da 100644
--- a/graph.c
+++ b/graph.c
@@ -442,7 +442,14 @@ void bar_graph_draw(struct graph *bg, cairo_t *cr)
 	nlabels = count_labels(bg->labels);
 	space_per_label = (x2 - x1) / (double) nlabels;
 
+	/*
+	 * Start bars at 0 unless we have negative values, otherwise we
+	 * present a skewed picture comparing label X and X+1.
+	 */
 	mindata = find_min_data(bg->labels);
+	if (mindata > 0)
+		mindata = 0;
+
 	maxdata = find_max_data(bg->labels);
 
 	if (fabs(maxdata - mindata) < 1e-20) {
@@ -452,8 +459,7 @@ void bar_graph_draw(struct graph *bg, cairo_t *cr)
 		return;
 	}
 
-	graph_draw_y_ticks(bg, cr, x1, y1, x2, y2, mindata, maxdata, 10, 1);
-
+	maxdata = graph_draw_y_ticks(bg, cr, x1, y1, x2, y2, mindata, maxdata, 10, 1);
 	i = 0;
 	for (lb = bg->labels; lb; lb = lb->next) {
 		int nvalues;
@@ -519,6 +525,15 @@ void line_graph_draw(struct graph *g, cairo_t *cr)
 	minx = find_xy_value(g, getx, mindouble);
 	maxx = find_xy_value(g, getx, maxdouble);
 	miny = find_xy_value(g, gety, mindouble);
+
+	/*
+	 * Start graphs at zero, unless we have a value below. Otherwise
+	 * it's hard to visually compare the read and write graph, since
+	 * the lowest valued one will be the floor of the graph view.
+	 */
+	if (miny > 0)
+		miny = 0;
+
 	maxy = find_xy_value(g, gety, maxdouble);
 
 	if (fabs(maxx - minx) < 1e-20 || fabs(maxy - miny) < 1e-20) {
@@ -836,7 +851,7 @@ static int xy_match(struct xyvalue *xy, int x, int y)
 	int xdiff = abs(xy->gx - x);
 	int ydiff = abs(xy->gy - y);
 
-	return xdiff <= 20 && ydiff <= 10;
+	return xdiff <= 10 && ydiff <= 10;
 }
 
 const char *graph_find_tooltip(struct graph *g, int x, int y)