From 3a07df265e238e35022b6c1e03eff839a783ee9e Mon Sep 17 00:00:00 2001
From: Yiwei Yang <40686366+victoryang00@users.noreply.github.com>
Date: Wed, 2 Aug 2023 21:37:12 -0700
Subject: [PATCH] Update README

---
 README | 20 ++++++++++++++------
 1 file changed, 14 insertions(+), 6 deletions(-)

diff --git a/README b/README
index 641d73278..29f2e36b5 100755
--- a/README
+++ b/README
@@ -1,6 +1,14 @@
-# Bede Kernel
-## Design
-1. DSA Migration impl
-2. on cgroup starting bede kthread
-3. on cgroup change, change the bede target
-4. let k8s change the change the cgroup procfs variable to change the migration target
\ No newline at end of file
+Bede Kernel
+
+Design
+1. TODO: DSA Migration impl, currently just migrate page async.
+2. on cgroup start, starting bede struct.
+3. on cgroup init procfs, init the policy_node instrumentation. Locally bind specially dealt with.
+4. let k8s change the cgroup procfs variable to change the migration target.
+
+Known Limitation
+1. on clone3 syscall, the cloned process may double the rss limitation. Python is not working, since it calls clone and detach child at very beginning.
+2. on file-backed mmap syscall, on page fault, the decision is not go through the policy_node path, thus invalid.
+
+Pitfalls
+1. Kernel 6.4.0 removes atomic irq https://lore.kernel.org/all/20230421174020.2994750-1-yosryahmed@google.com/, which makes numastat in hot path crash irq.