From c59f67d808034f8415f6a819fac9974c29a44afa Mon Sep 17 00:00:00 2001
From: Paolo Barbolini <paolo@paolo565.org>
Date: Tue, 8 Sep 2020 21:14:05 +0200
Subject: [PATCH] pool: use better defaults

* increases the max_size to r2d2' default of 10
* decreases the min_idle number of connections to 0 (was equal to max_size before)
* decreases the idle timeout from 10 minutes to 1 minute
---
 src/transport/smtp/transport.rs | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/src/transport/smtp/transport.rs b/src/transport/smtp/transport.rs
index 66006fe..9609774 100644
--- a/src/transport/smtp/transport.rs
+++ b/src/transport/smtp/transport.rs
@@ -150,7 +150,10 @@ impl SmtpTransportBuilder {
         let client = self.build_client();
         SmtpTransport {
             #[cfg(feature = "r2d2")]
-            inner: Pool::builder().max_size(5).build_unchecked(client),
+            inner: Pool::builder()
+                .min_idle(Some(0))
+                .idle_timeout(Some(Duration::from_secs(60)))
+                .build_unchecked(client),
             #[cfg(not(feature = "r2d2"))]
             inner: client,
         }