Smart Push limitation

Dear everyone,

I have one question about Smart Push.

I am trying to use smart push on form and run it after Save.

However, when I checked the jobs, it showed the error:

I have ticked on "Use Database Suppresion" also.

So my question is:

1. Is there any standard document that mentions the Smart Push's limitation?
2. How can I optimize the Smart Push

Note: I am using PBCS, so Groovy is not supported.

Thanks, and have a nice day!