DevTools is slow to startup

[jacob314]

DevTools is a bit slower to startup than expected. It is possible this is just a Flutter Web issue or it is possible we are serving which settings that defeat some caching of assets used by Flutter Web. For example, we need to make sure that that CanvasKit is cached rather than downloaded from the server each time.

Once DevTools renders it displays a spinner while sending off the following requests:

{jsonrpc: 2.0, method: getVersion, id: 9, params: {}}
{jsonrpc: 2.0, method: getVersion, id: 10, params: {}}
{jsonrpc: 2.0, method: getFlagList, id: 11, params: {}}
{jsonrpc: 2.0, method: getVM, id: 12, params: {}}
{jsonrpc: 2.0, method: getIsolate, id: 13, params: {isolateId: 1}}

At minimum we should only call getVersion once and we should try to ensure that all other requests are issued in parallel.

[grouma]

Note that there still seems to be a delay after getting a response for those initial requests. package:dwds responds to those requests almost immediately yet the spinner is still shown for a small period of time.