The following issues were fixed in Graph Visualiser:

1) Allow the user to set the row limit and chart line width.
2) Zoom should only be applied to X-axis, not both.
3) On clicking the 'Generate' button, the chart should return to its original zoom level.
4) Negative values are not displayed.

refs #7485

web/pgadmin/dashboard/__init__.py

@@ -174,6 +174,14 @@ class DashboardModule(PgAdminModule):
                              'details')
         )
 
+        self.graph_line_border_width = self.graphs_preference.register(
+            'graphs', 'graph_line_border_width',
+            gettext("Chart line width"), 'integer',
+            1, min_val=1, max_val=10,
+            category_label=PREF_LABEL_DISPLAY,
+            help_str=gettext('Set the width of the lines on the line chart.')
+        )
+
     def get_exposed_url_endpoints(self):
         """
         Returns:

web/pgadmin/dashboard/static/js/Graphs.jsx

@@ -233,6 +233,7 @@ export default function Graphs({preferences, sid, did, pageVisible, enablePoll=t
           errorMsg={errorMsg}
           showTooltip={preferences['graph_mouse_track']}
           showDataPoints={preferences['graph_data_points']}
+          lineBorderWidth={preferences['graph_line_border_width']}
           isDatabase={did > 0}
         />
       }
@@ -265,6 +266,9 @@ export function GraphsWrapper(props) {
       point: {
         radius: props.showDataPoints ? DATA_POINT_SIZE : 0,
       },
+      line: {
+        borderWidth: props.lineBorderWidth,
+      },
     },
     plugins: {
       legend: {
@@ -289,8 +293,11 @@ export function GraphsWrapper(props) {
       x: {
         reverse: true,
       },
+      y: {
+        min: 0,
+      }
     },
-  }), [props.showTooltip, props.showDataPoints]);
+  }), [props.showTooltip, props.showDataPoints, props.lineBorderWidth]);
   const updateOptions = useMemo(()=>({duration: 0}), []);
 
   const onInitCallback = useCallback(
@@ -353,5 +360,6 @@ GraphsWrapper.propTypes = {
   errorMsg: PropTypes.string,
   showTooltip: PropTypes.bool.isRequired,
   showDataPoints: PropTypes.bool.isRequired,
+  lineBorderWidth: PropTypes.number.isRequired,
   isDatabase: PropTypes.bool.isRequired,
 };