504 error trying to display a large workflow (works in FireCloud)

[mbookman]

I have been running the joint-discovery-gatk4.wdl in Terra over 4000 gVCFs. This workflow ultimately creates tens of thousands of child operations as the published intervals_list contains 10,187 intervals and there are 5 different scatters in this workflow over those 10,187 intervals.

When trying to bring up the workflow in Job Manager, the page fails to load (no error displayed, it just says "Authenticate" and "Sign In"). When I bring up the browser console, I can see:

Failed to load resource: the server responded with a status of 504 ()
main.9778a89cd2c9767f5a05.bundle.js:1 ERROR Error: Uncaught (in promise): Object: {"status":504,"title":"OK","message":"An unknown error has occurred. Please try again later."}
    at S (polyfills.97fa30f63aa53d84f512.bundle.js:1)
    at S (polyfills.97fa30f63aa53d84f512.bundle.js:1)
    at polyfills.97fa30f63aa53d84f512.bundle.js:1
    at t.invokeTask (polyfills.97fa30f63aa53d84f512.bundle.js:1)
    at Object.onInvokeTask (main.9778a89cd2c9767f5a05.bundle.js:1)
    at t.invokeTask (polyfills.97fa30f63aa53d84f512.bundle.js:1)
    at e.runTask (polyfills.97fa30f63aa53d84f512.bundle.js:1)
    at v (polyfills.97fa30f63aa53d84f512.bundle.js:1)
    at e.invokeTask [as invoke] (polyfills.97fa30f63aa53d84f512.bundle.js:1)
    at m (polyfills.97fa30f63aa53d84f512.bundle.js:1)

On the one hand, this seems to be a back-end error, but on the other hand I can view the workflow in FireCloud. If these are using different API calls, then please do turn this into an issue for the appropriate API.

Thanks!