Platform process manager - js.events

[raj231]

Hi, want to know more about js.events in platform process manager. During restart if js.events is renamed to js.events_backup, will that stop flow manager from starting? Why should we clear js.events and cache to restart flow manager?

[JuanS_OCS]

Hello @raj231,

While it is "safe" to back it up by renaming, beware you will be losing the historic data of your executions (when you click "History").

Instead of that, I would rather make a copy of the file and trim the file, to a level of "last X days" or "last X months".

Consider js.events as a database where it is recording your executions, and that is the data queried by FLow Manager when you click History. The more you remove, the more you won't be able to read anymore when you click "History". 

Additionally, you can consider to actually parse/read this data and create your own DB or SAS table, it might be useful, to analyse executions and compare performance, as good example.

[raj231]

Thank you for the detailed explanation. But I would like to know why should we rename an existing js.events file when we restart the process manager. As this was considered a solution whenever the platform process manager would not start giving out error messages. Please advise

[JuanS_OCS]

Hello @raj231,

I cannot give you the answer/solution to that question, since you probably better be asking it to whom provided you the solution.

What I can tell is that, if it this file is big enough, it might cause problems as:

• slowness loading the history of executions
• JVM errors
• timeouts
• and such...

The reasons is that this is a text file, which is read/wrote and loaded in sequential basis, hence some periodic maintenance in this file would help you with the health of this service.

Please note the fact I mentioned "periodic maintenance": always healthier to act pro-actively than react to errors.

Anyway, this is only for the Flow Manager, a client application. Just to be clear, js.events should not affect the availability of your server, just the client (because it is Java based)