https://community.esri.com/t5/arcgis-javascript-maps-sdk-questions/mapimagelayer-became-very-slow/m-p/1041374#M72242 <P>We have a silverlight application that consumes a map service from an enterprise ArcGIS Server.&nbsp; But it suddenly becomes very slow in earlier this year.&nbsp; Then we developed a testing application that uses ArcGIS API for JavaScript, by using&nbsp;MapImageLayer.&nbsp; But it returns&nbsp;mapimagelayer:image-fetch-error, unable to load image.&nbsp; However, when zooming in to a local area, the map does show up but takes long time.</P><P>In trouble shooting this, we developed another desktop application by using ArcGIS Runtime for .NET (ArcGISMapImageLayer) to test the issue is not within the server.&nbsp; The map can quickly shows up, without any issue.&nbsp; The speed is exactly like the silverlight application before the performance drops.&nbsp;&nbsp;</P><P>When testing ArcGIS API for Javascript, we did run on IE, Chrome, Firefox and Edge.&nbsp; The issue is persistent.</P><P>What are the possible reasons that running MapImageLayer of ArcGIS API for JavaScript in browser fails or slow but&nbsp;ArcGISMapImageLayer of&nbsp;ArcGIS Runtime for .NET maintains the fast performance?</P><P>Thanks!&nbsp;</P><P>&nbsp;</P> Sun, 28 Mar 2021 15:46:04 GMT swang 2021-03-28T15:46:04Z https://community.esri.com/t5/arcgis-javascript-maps-sdk-questions/mapimagelayer-became-very-slow/m-p/1041374#M72242 <P>We have a silverlight application that consumes a map service from an enterprise ArcGIS Server.&nbsp; But it suddenly becomes very slow in earlier this year.&nbsp; Then we developed a testing application that uses ArcGIS API for JavaScript, by using&nbsp;MapImageLayer.&nbsp; But it returns&nbsp;mapimagelayer:image-fetch-error, unable to load image.&nbsp; However, when zooming in to a local area, the map does show up but takes long time.</P><P>In trouble shooting this, we developed another desktop application by using ArcGIS Runtime for .NET (ArcGISMapImageLayer) to test the issue is not within the server.&nbsp; The map can quickly shows up, without any issue.&nbsp; The speed is exactly like the silverlight application before the performance drops.&nbsp;&nbsp;</P><P>When testing ArcGIS API for Javascript, we did run on IE, Chrome, Firefox and Edge.&nbsp; The issue is persistent.</P><P>What are the possible reasons that running MapImageLayer of ArcGIS API for JavaScript in browser fails or slow but&nbsp;ArcGISMapImageLayer of&nbsp;ArcGIS Runtime for .NET maintains the fast performance?</P><P>Thanks!&nbsp;</P><P>&nbsp;</P> Sun, 28 Mar 2021 15:46:04 GMT https://community.esri.com/t5/arcgis-javascript-maps-sdk-questions/mapimagelayer-became-very-slow/m-p/1041374#M72242 swang 2021-03-28T15:46:04Z