Question Unity 2022 - Extra Native memory allocation

Hi,
In 2022 we've changed IL2CPP to use Unity's native Memory Manager and its allocation tracking system to make its allocations for the Virtual Machine memory (this includes allocations to hold stuff like e.g. Managed Type information and e.g. the use of Generics can have a huge impact on that amount), instead of making these allocations in a way that was previously "Untracked". I.e. that amount should not be what the increase you see in XCode is, but just a shift from the "Untracked" bucket into the "Native Memory" bucket. That said, newer versions of the package should show those 103 MB as "Virtual Machine (IL2CPP)" memory on the summary page.

Which exact Unity versions did you capture from and in which version of the Memory Profiler Package did you open this in?

 

You can open both snapshots in 1.0, or even 1.1.0-pre.1, for more comparable data representation.
You can import snapshot from older Unity versions into the 2022 project via the Memory Profiler's menu bar button for importing, or just copy the file into the same snapshot folder (that's what import does).
You can also look at these two in comparison view and check the All Of Memory table.

 

That package version can't parse the IL2CPP VM Memory from the snapshot correctly, as it is reported differently than how the the Mono VM memory is reported and the 0.7.1 package version could not predict that. Consequently, it'll show that memory as native memory.

This should not affect how memory is reported and tracked. That said, captures taken on 2020.x that are still in that capture folder or imported into it would have a different, potentially less accurate, basis for their data.

In 2022.2 we closed most reporting gaps (i.e. memory allocated by Unity's systems should no longer be "Untracked") and the remaining "Untracked" amount is now no longer based on a single query to the OS to report the amount allocated by the app (which in some older versions was also not using quite the most accurate stat on all platforms). Instead it is based on going over all memory pages allocated by the app. This and fixes to the old query (which is still used for stats like the Memory Profiler Module's "System Used Memory" counter). We're quite confident that with that, we can at least confidently tell what we don't have concrete information on via our Memory Manager, where 2020 might still have been somewhat inaccurate or less precise, also depending on the platform.

So the way the data gets reported changed with the Unity version the snapshot was taken from. The package version is irrelevant to the captured data, but the newer package versions are adjusted to parse and present the data in a way that is more consistent with the discoveries that led to the adjustment to the reported data. That, and then there are Bugfixes. So even if the snapshot file doesn't change, the newer package versions parse that same data in a way that is usually (unless affected by bugs) more accurate.

In this case I think the IL2CPP VM Memory was:

• Not present / Untracked in 2020
  • Plus Untracked was less accurate
• Present in 2022 but parsed as Native memory in 0.7
• Parsed as Managed Memory in the Summary in 1.0
  • Therefore NOT tracked as Native Memory

Similarly, the Executables & DLLs has been made more accurate, both via reporting the data for them differently and by parsing it differently in the package.

Long winded way of saying: try using the latest package version for comparing the snapshots and largely ignore what older package versions said. There's always the possibility of bugs but I'd base them on other observations, e.g. if stuff doesn't add up within a package version or conflict with native platform profilers.