Heap out of bounds ， use motoko

[bitbruce]

@ggreif

When preupgrade is running in a fragmented heap, there may not be enough capacity to push all the information into stable variables and externalize them into a monolithic buffer (which then will be copied to the stable memory space). We are aware of these two problems:

• need to run an explicit GC before preupgrade (and possibly after)
• need to use a streaming technique to write stable variables to stable memory.

I am working on the former and @claudio is about to tackle the latter.

This issue still seems to be unresolved. When I upgrade the same wasm (motoko), the canister with little memory usage can be upgraded successfully, but the canister with 70M memory usage cannot be upgraded, and the error “Canister qhssc-vaaaa-aaaak-adh2a-cai trapped: heap out of bounds” is reported. This problem has been encountered several times.

Memory allocation: 0
Compute allocation: 0
Freezing threshold: 2_592_000
Memory Size: Nat(70311386)
Balance: 14_558_822_050_955 Cycles
Module hash: 0xa2edf6ff68c0b00dc9e971602d7542f542289a62c6d108d60dda64273406e8b0