From d7ed9d8e0130f0bf486d4085da4281af67fb9400 Mon Sep 17 00:00:00 2001
From: Bojan Serafimov <bojan.serafimov7@gmail.com>
Date: Wed, 16 Mar 2022 17:40:19 -0400
Subject: [PATCH] cleanup

---
 pageserver/src/bin/psbench.rs | 114 ++++++++++++++++++----------------
 1 file changed, 60 insertions(+), 54 deletions(-)

diff --git a/pageserver/src/bin/psbench.rs b/pageserver/src/bin/psbench.rs
index 4bc80caccc..6a5124e41b 100644
--- a/pageserver/src/bin/psbench.rs
+++ b/pageserver/src/bin/psbench.rs
@@ -3,6 +3,7 @@
 //! Usually it's easier to write python perf tests, but here the performance
 //! of the tester matters, and the API is easier to work with from rust.
 use std::{io::{BufRead, BufReader, Cursor}, net::SocketAddr};
+use tokio::io::{AsyncReadExt, AsyncWriteExt};
 use bytes::{Bytes, BytesMut};
 use clap::{App, Arg};
 use std::fs::File;
@@ -16,6 +17,59 @@ pub fn read_lines_buffered(file_name: &str) -> impl Iterator<Item = String> {
         .map(|result| result.unwrap())
 }
 
+pub async fn get_page(
+    pagestream: &mut tokio::net::TcpStream,
+    lsn: &Vec<u8>,
+    page: &Vec<u8>,
+) -> anyhow::Result<Vec<u8>> {
+    let msg = {
+        let query = {
+            use bytes::buf::BufMut;
+            let mut query = BytesMut::new();
+            query.put_u8(2);  // Specifies get_page query
+            query.put_u8(0);  // Specifies this is not a "latest page" query
+            for byte in lsn {
+                query.put_u8(*byte);
+            }
+            for byte in page {
+                query.put_u8(*byte);
+            }
+            query.freeze()
+        };
+
+        let mut buf = BytesMut::new();
+        let copy_msg = BeMessage::CopyData(&query);
+        BeMessage::write(&mut buf, &copy_msg)?;
+        buf.freeze()
+    };
+
+    pagestream.write(&msg).await?;
+
+    let response = match FeMessage::read_fut(pagestream).await? {
+        Some(FeMessage::CopyData(page)) => page,
+        _ => panic!("AAAAA"),
+    };
+
+    let page = {
+        let mut cursor = Cursor::new(response);
+        let tag = cursor.read_u8().await?;
+        if tag != 102 {
+            panic!("AA");
+        }
+
+        let mut page = Vec::<u8>::new();
+        cursor.read_to_end(&mut page).await?;
+        dbg!(page.len());
+        if page.len() != 8 * 1024 {
+            panic!("AA");
+        }
+
+        page
+    };
+
+    Ok(page)
+}
+
 #[tokio::main]
 async fn main() -> Result<()> {
 
@@ -71,10 +125,8 @@ async fn main() -> Result<()> {
         })
         .collect();
 
-    let (some_lsn, some_page) = lsn_page_pairs[0].clone();
-
+    // Get raw TCP connection to the pageserver postgres protocol port
     let mut socket = tokio::net::TcpStream::connect("localhost:15000").await?;
-    println!("AYY got socket");
     let (client, conn) = tokio_postgres::Config::new()
         .host("127.0.0.1")
         .port(15000)
@@ -83,61 +135,15 @@ async fn main() -> Result<()> {
         .connect_raw(&mut socket, tokio_postgres::NoTls)
         .await?;
 
-    let query = format!("pagestream {} {}", tenant_hex, timeline);
+    // Enter pagestream protocol
+    let init_query = format!("pagestream {} {}", tenant_hex, timeline);
     tokio::select! {
         _ = conn => panic!("AAAA"),
-        _ = client.query(query.as_str(), &[]) => (),
+        _ = client.query(init_query.as_str(), &[]) => (),
     };
 
-    println!("AYYYYYYYYYYYY");
-
-    let msg = {
-        let query = {
-            use bytes::buf::BufMut;
-            let mut query = BytesMut::new();
-            query.put_u8(2);  // Specifies get_page query
-            query.put_u8(0);  // Specifies this is not a "latest page" query
-            for byte in some_lsn {
-                query.put_u8(byte);
-            }
-            for byte in some_page {
-                query.put_u8(byte);
-            }
-            query.freeze()
-        };
-
-        let mut buf = BytesMut::new();
-        let copy_msg = BeMessage::CopyData(&query);
-        BeMessage::write(&mut buf, &copy_msg)?;
-        buf.freeze()
-    };
-
-    use tokio::io::{AsyncReadExt, AsyncWriteExt};
-    socket.write(&msg).await?;
-
-    let response = match FeMessage::read_fut(&mut socket).await? {
-        Some(FeMessage::CopyData(page)) => page,
-        _ => panic!("AAAAA"),
-    };
-
-    let page = {
-        let mut cursor = Cursor::new(response);
-        let tag = cursor.read_u8().await?;
-        if tag != 102 {
-            panic!("AA");
-        }
-
-        let mut page = Vec::<u8>::new();
-        cursor.read_to_end(&mut page).await?;
-        dbg!(page.len());
-        if page.len() != 8 * 1024 {
-            panic!("AA");
-        }
-
-        page
-    };
-
-    print!("yay done");
+    let (some_lsn, some_page) = lsn_page_pairs[0].clone();
+    let _page = get_page(&mut socket, &some_lsn, &some_page).await?;
 
     Ok(())
 }