IMAP "Push" Overhead & Other Questions

[BigbirdPhila]

Is there a consensus on the amount of drain IMAP PUSH puts on a battery compared to a straight polling approach?

Is cellular PUSH a bigger drain than WiFi PUSH?

Is PUSH considered bulletproof, or should a polling schedule also be used to avoid missing emails?

Aqua has a "Push mail session duration" parameter.  What is it and what are the tradeoffs in its allowed settings (30 minutes, 1 hour, 2 hours)?

Thanks for your help. 

[StR]

I  can answer a few of these questions.
Push uses more battery then scheduled sync.
How much more depends on many parameters.  Only you can figure out by running it for some time.

The developer recommends having scheduled sync enabled even when push is enabled, to catch what could be missed by Push. (There could be some conditions (network, server, etc.) that could lead to that.)
I'd say 30 or 60 minute sync frequency should be sufficient.

[Kostya Vasilyev]

Right, I'd say you can give it a try and turn off if there are issues.

The most important this is to keep the "messages to sync" setting reasonable -- this is how many most recent messages the app "looks at" on the server, every time it syncs mail from either scheduled or push.

The default is 50 (per folder), 100 would work too I think -- but I've seen people set this to 500 or 1000 and complain about battery drain

[BigbirdPhila]

Aqua has a "Push mail session duration" parameter.  What is it and what are the tradeoffs in its allowed settings (30 minutes, 1 hour, 2 hours)?

Does anyone have an answer to the above question?

[Kostya Vasilyev]

Re: Aqua has a "Push mail session duration" parameter.  What is it and what are the tradeoffs in its allowed settings (30 minutes, 1 hour, 2 hours)?

IMAP guarantees that an established and logged in connection will not be disconnected by the mail server for at least 30 minutes.

I'd say leave it at that, or try 1 hour. This won't have a big effect on battery usage - since even "every 25 minutes" (which is what the "30 minutes" setting actually does) is not _that_ often, compared to everything else that push mail has to do.