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Any idea what might have caused/be causing my CPU to suddenly get completely eaten up in AUM?
It's not an issue of anything new being introduced, it's an issue of why is this suddenly happening when I'm using the same apps, the same way? I took a screen recording but it's not very helpful and would probably just lead to more confusion.
So to give a good starter example; usually on my walk home from the bus stop I lay down the foundation for a track. Today it was freezing balls out but I threw down a super sweet bassline and some drums from Groovebox and threw on a reverb (from the recently released bundle that had everyone (including me) throwing their arms up and tripping over charging cables on a mad dash to smash "BUY" - that's hopefully enough to spur someone's memory as i can't find my phone)
Don't worry that's all relevant. I know the reverb is rather CPU heavy but I managed to turn the mix down almost all the way so the actual effect was fairly subtle and the CPU impact was somewhere around 50% with all the other apps running. Around then my fingers began getting frostbite so I put the phone in my pocket and left it playing so I could come up with some brain-beats to turn into tangible tunes when I got home.
It's about a 20 minute walk home, the whole time the track was looping perfectly fine w/ reverb on. About 5 minutes after I got inside I started hearing audio doing "the crackles," even though I hadn't touched it. The crackles quickly progressed to a complete feedback blast that I had to rush to fix. I fixed it just by muting/swiping left on the reverb and things went back to playing...
for a BIT. But then that started happening with my other apps. I only had mela, LK running a pattern through to Synthmaster Player (find it a lot less CPU intensive than the full SM1) and Pure Acid running a bassline. And Groovebox in the background sending drums through IAA. I use a similar setup with a few extra apps + fx without crackling all the time (should loaded it to see what happenn}
Nonetheless my CPU starts maxing out again. I chopped out Synthmaster cuz that's pretty heavy on the CPU and replaced it with Viking Synth. Got another 10 minutes of a jam in before CPU started to spike again. (Note I've had the reverb FX off this whole time).
Then i reloaded AUM completely. Kept all the apps deactivate that I wasn't using n brought 2 in one at a time so at this point it was legit just LK feeding midi to Viking and Pure Acid. Things were good enough to put the reverb back on but it spiked immediately so I switched it out for J chorus which uses like no CPU and restarted again. Eventually it got to the point where just using more than one app maxed out the CPU.
other tidbits for possible ID
-apps would spike CPU as soon as I loaded them even if they weren't doing anything
-the same app progressively used more and more CPU the longer i jammed
-i ate too much candy today 
any tips would ber much appreciado
Comments
If you tap the AUM DSP meter, then select Node Statistics, you can see which components are using the most CPU.
Have you possibly changed latency (buffer size) or sample rate (44.1, 48 kHz, etc.)? iOS may have done that for you, if you've updated recently.
Are you running any other apps in the background that may be using CPU. AUM's DSP percentage is actually based on the free time available, so a heavy background app could drive the DSP up toward 100%. Try force-quitting everything (swipe icons of the top of the App Switcher), then see if performance improves. You might also try Airplane Mode.
What iOS/iPadOS version are you using, on which device? Did you update recently?
Apps will spike CPU on loading because they are initializing data, and possibly GUI graphics.
I suspect the cold might have something to do with the slowing down of your processor.
Batteries also lose power/charge in the cold.
I remember a story of a woman in scandinavia who had here iphone 4 screen shattered by the freezing cold. Apple refused warranty stating the operating temperatures in the manual were exceded.
You didn't mention rebooting your phone. If you didn't try that already it should be the first thing to try when something odd like that happens. Swipe closed all apps, then power the phone off and then back on.
Mobile devices change cpu throttling , priority, core assignment in response to power consumption and battery level. You mentioned that you were running on battery. It may have been a response to battery level/consumption. As you used up battery it may have throttled down your processor to preserve battery.
no changes in settings, as mentioned it became unusable with any apps. so while it's good to know about node statistics for future (i usually just do the math in my head whenever i turn on a new plugin and subtract the old % from the new) if i've only got one or two apps plugged in and my cpu's over 100% then i know something else is going on. no other apps running. didn't do anything that would usually influence CPU processing.> @Alfred said:
possible, i'm pretty familiar with how my iphone behaves in the cold though. if i'm using it the battery will drain by about 10% per minute once it approaches zero degrees. if I don't turn the screen on then for some reason it hibernates and will still last around 20-25% the duration that it normally would but if I happen to turn it on during that time it'll be at 1% and the screen will turn on just long enough to laugh at me before it dies. idk if this sounds weird but i actually do that walk all the time with aum or gadget playing in the background cuz my fingeres get too cold after laying down bass & drums or whatever foundation> @wim said:
aye yeah that is usually what i would do but due to the above situation i didn't think my phone would turn back on again, which wouldnt be a huge deal but then i wouldn't get to repetitively enjoy the same 8 bars for the final 1200 meters! @espiegel123 said:
would that mean my battery's just dying? i don't think i've ever really used it while it's not on battery so thatd be a new thing btu my battery life % did drop significantly in what seemed to be overnight a while back. but yeah maybe once or twice when i've had liike a two hour long aum jam and had to dash to plug it in before it died but usually im on battery
i feel like the unfiltered verb just does something weitrd to my processor that jacks it up permanently until i'm able to restart . fortunately thanks to loopy's easy inactivation of apps ive been able to enjoy it via loopy in a way that i wouldnt be able to otherwrise