diff --git a/README.md b/README.md
index 26fabf2ed..3777dbef2 100644
--- a/README.md
+++ b/README.md
@@ -102,6 +102,7 @@ curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh -s -- --default-t
 echo "source \$HOME/.cargo/env" >> $HOME/.bashrc && source $HOME/.cargo/env
 
 rustup install $(cat ss-rust/src/main/rust/shadowsocks-rust/rust-toolchain)
+rustup default $(cat ss-rust/src/main/rust/shadowsocks-rust/rust-toolchain)
 rustup target install armv7-linux-androideabi aarch64-linux-android i686-linux-android x86_64-linux-android
 ```
 
diff --git a/gradle.properties b/gradle.properties
index 2b95ef922..4e238ea2a 100644
--- a/gradle.properties
+++ b/gradle.properties
@@ -15,6 +15,7 @@
 RELEASE_KEY_PASSWORD=android
 RELEASE_KEY_ALIAS=androidkey
 RELEASE_STORE_PASSWORD=android
+org.gradle.jvmargs=-XX:MaxPermSize=16384m
 org.gradle.daemon=true
 org.gradle.parallel=true
 org.gradle.configureondemand=false