From e4d25b207d4a4cc16b0ba8aa598e458458d5d2b2 Mon Sep 17 00:00:00 2001
From: Bryan Stitt <bryan@satoshiandkin.com>
Date: Tue, 6 Sep 2022 20:50:37 +0000
Subject: [PATCH] better default connection counts

---
 web3_proxy/src/app.rs            | 10 ++++++----
 web3_proxy/src/bin/web3_proxy.rs |  4 ++--
 web3_proxy/src/config.rs         | 11 ++++++-----
 3 files changed, 14 insertions(+), 11 deletions(-)

diff --git a/web3_proxy/src/app.rs b/web3_proxy/src/app.rs
index 7007a0b2..69fbf621 100644
--- a/web3_proxy/src/app.rs
+++ b/web3_proxy/src/app.rs
@@ -144,6 +144,7 @@ impl Web3ProxyApp {
     pub async fn spawn(
         app_stats: AppStats,
         top_config: TopConfig,
+        num_workers: u32,
     ) -> anyhow::Result<(
         Arc<Web3ProxyApp>,
         Pin<Box<dyn Future<Output = anyhow::Result<()>>>>,
@@ -156,13 +157,13 @@ impl Web3ProxyApp {
 
         // first, we connect to mysql and make sure the latest migrations have run
         let db_conn = if let Some(db_url) = &top_config.app.db_url {
-            let db_min_connections = top_config.app.db_min_connections;
+            let db_min_connections = top_config.app.db_min_connections.unwrap_or(num_workers);
 
             // TODO: what default multiple?
             let redis_max_connections = top_config
                 .app
                 .db_max_connections
-                .unwrap_or(db_min_connections * 4);
+                .unwrap_or(db_min_connections * 2);
 
             let db =
                 get_migrated_db(db_url.clone(), db_min_connections, redis_max_connections).await?;
@@ -201,12 +202,13 @@ impl Web3ProxyApp {
 
                 let manager = RedisConnectionManager::new(redis_url.as_ref())?;
 
-                let redis_min_connections = top_config.app.redis_min_connections;
+                let redis_min_connections =
+                    top_config.app.redis_min_connections.unwrap_or(num_workers);
 
                 let redis_max_connections = top_config
                     .app
                     .redis_max_connections
-                    .unwrap_or(redis_min_connections * 4);
+                    .unwrap_or(redis_min_connections * 2);
 
                 // TODO: min_idle?
                 // TODO: set max_size based on max expected concurrent connections? set based on num_workers?
diff --git a/web3_proxy/src/bin/web3_proxy.rs b/web3_proxy/src/bin/web3_proxy.rs
index 0057fb8a..923f6d86 100644
--- a/web3_proxy/src/bin/web3_proxy.rs
+++ b/web3_proxy/src/bin/web3_proxy.rs
@@ -65,7 +65,7 @@ fn run(
     // start tokio's async runtime
     let rt = rt_builder.build()?;
 
-    let num_workers = rt.metrics().num_workers();
+    let num_workers = rt.metrics().num_workers() as u32;
     debug!(?num_workers);
 
     rt.block_on(async {
@@ -76,7 +76,7 @@ fn run(
         let app_frontend_port = cli_config.port;
         let app_prometheus_port = cli_config.prometheus_port;
 
-        let (app, app_handle) = Web3ProxyApp::spawn(app_stats, top_config).await?;
+        let (app, app_handle) = Web3ProxyApp::spawn(app_stats, top_config, num_workers).await?;
 
         let frontend_handle = tokio::spawn(frontend::serve(app_frontend_port, app));
 
diff --git a/web3_proxy/src/config.rs b/web3_proxy/src/config.rs
index df1bda6d..a3a713a5 100644
--- a/web3_proxy/src/config.rs
+++ b/web3_proxy/src/config.rs
@@ -5,7 +5,6 @@ use argh::FromArgs;
 use derive_more::Constructor;
 use ethers::prelude::TxHash;
 use hashbrown::HashMap;
-use num::One;
 use serde::Deserialize;
 use std::sync::Arc;
 use tokio::sync::broadcast;
@@ -47,9 +46,10 @@ pub struct AppConfig {
     pub chain_id: u64,
     pub db_url: Option<String>,
     /// minimum size of the connection pool for the database
-    #[serde(default = "u32::one")]
-    pub db_min_connections: u32,
+    /// If none, the number of workers are used
+    pub db_min_connections: Option<u32>,
     /// minimum size of the connection pool for the database
+    /// If none, the minimum * 2 is used
     pub db_max_connections: Option<u32>,
     #[serde(default = "default_default_requests_per_minute")]
     pub default_requests_per_minute: u32,
@@ -63,9 +63,10 @@ pub struct AppConfig {
     pub public_rate_limit_per_minute: u64,
     pub redis_url: Option<String>,
     /// minimum size of the connection pool for the cache
-    #[serde(default = "u32::one")]
-    pub redis_min_connections: u32,
+    /// If none, the number of workers are used
+    pub redis_min_connections: Option<u32>,
     /// maximum size of the connection pool for the cache
+    /// If none, the minimum * 2 is used
     pub redis_max_connections: Option<u32>,
     #[serde(default = "default_response_cache_max_bytes")]
     pub response_cache_max_bytes: usize,