From 0d5041ca4a972a946244643db738e6d35b0d114e Mon Sep 17 00:00:00 2001
From: Antoine Poinsot <darosior@protonmail.com>
Date: Tue, 22 Aug 2023 15:41:26 +0200
Subject: [PATCH] bitcoin: looper: avoid large sleeps when bitcoind is syncing

Sleeping for 30 whole seconds impedes the shutdown check. Sleep only .5s
but still only do poll bitcoind one every 30s when it's syncing.
---
 src/bitcoin/poller/looper.rs | 24 +++++++++++++++++++-----
 1 file changed, 19 insertions(+), 5 deletions(-)

diff --git a/src/bitcoin/poller/looper.rs b/src/bitcoin/poller/looper.rs
index c039b06c..3a419a6f 100644
--- a/src/bitcoin/poller/looper.rs
+++ b/src/bitcoin/poller/looper.rs
@@ -306,6 +306,16 @@ fn maybe_initialize_tip(bit: &impl BitcoinInterface, db: &impl DatabaseInterface
     }
 }
 
+fn sync_poll_interval() -> time::Duration {
+    // TODO: be smarter, like in revaultd, but more generic too.
+    #[cfg(not(test))]
+    {
+        time::Duration::from_secs(30)
+    }
+    #[cfg(test)]
+    time::Duration::from_secs(0)
+}
+
 /// Main event loop. Repeatedly polls the Bitcoin interface until told to stop through the
 /// `shutdown` atomic.
 pub fn looper(
@@ -329,7 +339,15 @@ pub fn looper(
         let now = time::Instant::now();
 
         if let Some(last_poll) = last_poll {
-            if now.duration_since(last_poll) < poll_interval {
+            let time_since_poll = now.duration_since(last_poll);
+            let poll_interval = if synced {
+                poll_interval
+            } else {
+                // Until we are synced we poll less often to avoid harassing bitcoind and impeding
+                // the sync. As a function since it's mocked for the tests.
+                sync_poll_interval()
+            };
+            if time_since_poll < poll_interval {
                 thread::sleep(time::Duration::from_millis(500));
                 continue;
             }
@@ -345,10 +363,6 @@ pub fn looper(
             );
             synced = sync_progress == 1.0;
             if !synced {
-                // Avoid harassing bitcoind..
-                // TODO: be smarter, like in revaultd, but more generic too.
-                #[cfg(not(test))]
-                thread::sleep(time::Duration::from_secs(30));
                 continue;
             }
         }