The initial Sparrow target platform was intended to have 4MiB of memory. A production build of the included services fit in <2MiB of memory but due to the overhead of CAmkES and the rootserver boostrap mechanism actually require ~2x that to reach a running state. The kmem.sh script can be used to analyze memory use. These services should easily fit in <1MiB but due to CAmkES overhead (e.g. per-thread cost) are significantly bloated. We use kmem and the bloaty tool to evaluate memory use. Reducing memory use to <1MiB likely requires replacing CAmkES by a native Rust framework like embassy.
We also expect that replacing CAmkES C-based templates by native Rust code will significantly reduce memory use (as well as improve robustness by extending the scope of the borrow checker). The RPC mechanism used for communication between applications and the SDKRuntime is a prototype of a native Rust implementation that demonstrates this.