Office Hours Transcript: 2021-07-01

Well, I don’t used the latest version of Realm

Yeah working

Emergency_Backup_Murphy left

I see the emergency backup

do you see the original me?

yes

OK, thought maybe the chat broke down or something

I prefer the beta.hack.chat interface

Anyway, I don’t use the latest version of Realm

it’s possible you’re seeing some Realm bug, though I’m surprised that layout inflations would be the culprit, unless you’re doing Realm I/O in a view constructor

So that could definitely be a problem too

unless you’re doing Realm I/O in a view constructor

_<

I’ll try to capture a trace now

I’ll report back

So just launching the app on a Xiaomi phone, it’s already using 160MB of memory

Java: 15MB, Native: 50MB, Graphics: 18MB, Stack: 0.09MB, Code: 41.2MB, Others: 7MB

odd, that doesn’t seem to add up to 160MB

wonder where the other ~30MB went

anyway, 50MB native feels like an outlier, but I haven’t had a need to do this type of memory analysis in a while

Now, I’ve scrolled through the main recyclerview, 200 elements

And it’s using 271MB of memory

what is the new breakdown? did that mostly go to Native?

Java: 25MB, Native: 111MB, Graphics: 82MB, Stack: 0.1MB, Code: 39MB, Others: 8.2MB

Wait, could it be the Fresco library for loading images?

Fresco uses native code IIRC

at least back in the day, they were using that for what amounted to an in-memory cache

Because I have an image in each recyclerview element

Even if I trigger the garbage collection, the Native allocation still sits at 107MB

you might want to play around with Fresco cache settings (https://frescolib.org/docs/caching.html) and see if that changes things

If I turn off the screen, the Graphics memory goes down to 40MB

Nice, thanks for the link

I can’t tell if they have an API for controlling the cache size, though they should

https://frescolib.org/docs/configure-image-pipeline.html

Apparently, you need to implement MemoryTrimmableRegistry

ah, OK

if you have a way to get the current ImagePipelineConfig, you might see if you can log what the existing MemoryCacheParams values are

another quick-and-dirty test would be to comment out loading those images in your RecyclerView and see what the results are

if the memory problems go away, Fresco caching is your culprit, most likely

if the memory problems are still there, assuming you commented out Fresco’s bits, then Fresco won’t be the problem

Good idea

I’m interested in this problem because it seems that some battery managers are killing my app due to high memory usage

Kafran joined

sudokai: that’s not surprising

Thanks Mark!

sudokai: let me take a question from Kafran, and I’ll be with you in a bit

Kafran: hi! how can I help you today?

Hello Professor. Still studying =)
Professor I asked on the forum these days… I’m having difficulties to understand Classes Relationship on the OOP subject. Where could I read about composition, association and aggregation and its UML diagrams (=

I learned those topics over 20 years ago, so I am not up to date on the best current resources for learning OO concepts

Its not an Android question >.<
For what I can tell by reading the forum you’re a little skeptical about architecture (:

I would phrase it more that software architecture is a lot more "fuzzy" than some people think

if I asked five developers to show me how to do MVP in Android, I might get at least four distinctly different approaches

and none are necessarily right or wrong

so, in term of the "MV-whatever" sorts of architecture discussions, my reaction tends to be ¯\_(ツ)_/¯

I’m still learning the basics but with an eye on these things as these are fundamental to get a job =/

well, the architecture that will matter is the architecture used by your employer, and that may vary by employoer

er, employer

personally, I would focus more on having some pattern for how you set up your apps, for the sorts of samples that you might show a prospective employer as a portfolio

in other words, demonstrate good code organization skills, with some sort of layered approach

as opposed to, say, doing database I/O directly in an activity

Mark’s Exploring Android book is fantastic

sudokai, yes, I’m doing it

I wish all technical books were written in this way

along side with a coure I bought here in Brazil

course(

sudokai: thanks! and there I’m focusing less on the details of the architecture style and more on just following Google’s recommended layers

Well, I gtg! Thanks Mark, see you around!

sudokai left

Kafran: whether your particular style is MVVM or MVI or MVP or MVC or something else is unlikely to matter in an interview setting, because you are going to need to adapt to what that employer wants you to use

Ok. Thanks.

just be reasonably organized, and I would not expect you to encounter problems as a result of any specific choices that you make

I pretty anxious right now

I’m*

Mark, Exploring Android and Elements of Jetpack, should I follow both at same time?

you could, but that might be a bit much at once