Running slow on iPad Pro when charging

[CC Hogan]

I am not absolutely positive about this, but I have been suffering from Affinity Photo running slow with lag, but it appears to be only when I have my charger plugged in.

Anyone else have this? I am doing some artwork 5000 square at 300 with quite a few layers. Most of them pixel paint layers.

This is the 2ng gen iPad with the current iOS (12.4? ish?)

All the best

 

CC

[Dan C]

Hi CC Hogan

This isn't som,ething I've heard of before - in order to best test this could you please upload a copy of your .afphoto file to the following link so I can test directly with your layers etc? Thanks in advance!

https://www.dropbox.com/request/q0HjF3G10mox5qgmUlkp

[CC Hogan]

Okay - done that.  I had this the other day on a different (but similar file), but I didn't think about it until it happened again yesterday. I thought it was just one of those moments!

When it happened, I noticed that the screen on the iPad was getting warm under my hand, so perhaps this is a mixture of a large (ish) file and the charging.

I had been working on it for an hour maybe?

I am using the larger Apple charger - the 30w one.

[Dan C]

Thanks for your file - I've been testing this here using a third Gen iPad Pro & the 87W MBP charger. At first there was no noticeable difference with or without charging, however after around 1hour I noticed the app started to slow slightly, and my CPU usage (shown in a third party app) dropped.

At this time, the iPad was noticeably hot to the touch, and I suspect this is the CPU thermal throttling - with both the Affinity app using as much resources as possible and the battery charging at a higher rate/wattage that usual - the iPad is overheating slightly and throttling back the CPU speeds to account for this.

Unfortunately not much can be done regarding this, as cooling/throttling is all taken care of by Apple/iOS and we have no control over this - my apologies!

[CC Hogan]

Thanks, Dan - sorry about my late response - I missed a notification.

Since I posted this, I have been suffering sporadic slowdowns without charging and without the iPad getting hot. Just now it was on a 300 dpi 8000x4000 image with only 4 pixel layers. Suddenly it was lagging, and when I returned to the home screen, it took about 3 minutes to save. Once it had, then it seemed to be okay again.

you mentioned that Photo always uses as much resources as possible - could there be occasional resource fights going on with any background processes? (Sorry, I am a bit ignorant about iOS!)

[Dan C]

No problem at all

I'm sorry to hear this, our QA team have been testing documents roughly this size and have reported similar issues - these are logged with our development team and we're working hard to put this right!

13 hours ago, CC Hogan said:

could there be occasional resource fights going on with any background processes? (Sorry, I am a bit ignorant about iOS!)

There certainly could be, but I too am far from the authoritative figure on iOS - AFAIK we use all available system resources, but as for the hierarchy of which processes come first I don't believe Apple publicly share this information - apologies!