Simplified fix for issue 803

[cmadam]

Why are these changes needed?

This provides a simplified, minimal fix for issue #803

Related issue number (if any).

#803

[touma-I]

Please consider using environment variable as below. This keep the default at 100 (as it is now) but then allows you to set an environment variable to increate the number of actors if needed

Suggested change

	RAY_MAX_ACTOR_LIMIT = 10000
	RAY_MAX_ACTOR_LIMIT = int (os.environ.get("RAY_MAX_ACTOR_LIMIT", '100'))

[cmadam]

I do not see a benefit from using an additional environment variable. First, setting 100 as the default means issue #803 will occur by default, requiring users to read the documentation, locate the issue, and define a new environment variable to fix it. Second, Ray already uses an environment variable to define the RAY_MAX_LIMIT_FROM_API_SERVER constant here. Playing with this environment variable might allow us to change the max limit value, but I do not see what is the advantage of doing so.

[cmadam]

@touma-I : I can see that @dtsuzuku-ibm has opened an identical issue (#858) and a pull request (#859) with exactly the same fix as proposed here.

[touma-I]

Thanks @cmadam This is exactly what we need so we can just address the issue we are facing. I encourage you to consider the comment to use an environment variable though. This way we can use a default and if we want to overwrite the default, we can do so without rebuilding the code. Let me know what you think.