functions runtime slow to start after change deteceted

After making a change to a file, the functions runtime is slow to restart.

Repro steps

Provide the steps required to reproduce the problem

1. Install the functions runtime as part of an Azure Web App

2. Make a change to a file

Expected behavior

I’d expect that the runtime would go from starting to running relatively quickly.

Actual behavior

It’s sometimes absurdly slow (15-20min), even when changing a single file.

Related information

I’m running functions written in Node on Functions 1.0.10690. I see this issue mainly if I need to debug and make a quick change through FTP. When I deploy using my CI server, which uses Web Deploy, this seems to happen less often.

I also tend to see this error in my logs during this change from starting to pending:

Failed to copy job files: System.Threading.ThreadAbortException: Thread was being aborted.
   at Kudu.Core.Infrastructure.OperationManager.Attempt[T](Func`1 action, Int32 retries, Int32 delayBeforeRetry, Func`2 shouldRetry)
   at Kudu.Core.Infrastructure.OperationManager.Attempt(Action action, Int32 retries, Int32 delayBeforeRetry)
   at Kudu.Core.Jobs.BaseJobRunner.CacheJobBinaries(JobBase job, IJobLogger logger)

[mathewc]

I’ve updated the install step wiki with a note about this as well.

[jamesdixon]

@mathewc that appears to have worked perfectly! My jobs do have a number of NPM dependencies, so that would explain things.

I appreciate your help!

Cheers.