Policy evaluation at scale needs to be able to set memory limits
so that a bad policy does not hog memory or to ensure that
policy evaluation itself does not use too much memory which could
cause other components to suffer.
This PR introduces capability to set and enforce global memory limits.
It also lays the groundwork for enabling per evaluation limits in future.
Once a global memory limit is set, Regorus maintains per thread counters
to track memory activity (allocation, deallocation) of a thread.
These counters are periodically flushed to global memory counters.
Per thread counters avoid the contention that updating global counters
on each alloc/free would cause.
Policy evaluation periodically checks these counters and raises errors
if allocated memory has exceeded the configured limit.
Currently memory limit capability is exposed only to FFI and C#.
Also update mimalloc to v2.2.6
Signed-off-by: Anand Krishnamoorthi <anakrish@microsoft.com>
This PR implements widely accepted Rust programming practices for
dealing with panics across ABI (programming language) boundaries.
- Add panic_guard.rs to wrap FFI calls and prevent panic across FFI/ABI boundary (undefined behavior).
- Capture per-thread backtraces via a temporary panic hook
- After a panic, subsequent invocations are poisoned.
- Integrate with_unwind_guard across the engine, schema registry, and target registry exportis
Signed-off-by: Anand Krishnamoorthi <anakrish@microsoft.com>