rpc/server: Enlarge recv buffer to 81920 bytes.

src/rpc/server.rs

@@ -31,7 +31,7 @@ async fn accept(
 ) -> Result<()> {
     loop {
         // Nasty size
-        let mut buf = vec![0; 2048 * 10];
+        let mut buf = vec![0; 8192 * 10];
 
         let n = match stream.read(&mut buf).await {
             Ok(n) if n == 0 => {