From: Matt Corallo <git@bluematt.me>
Date: Tue, 8 Nov 2022 00:53:41 +0000 (+0000)
Subject: Set per-table autovacuum thresholds low
X-Git-Url: http://git.bitcoin.ninja/index.cgi?a=commitdiff_plain;h=458bb038baf4092b3eea0e2da62e50247af35cdb;p=rapid-gossip-sync-server

Set per-table autovacuum thresholds low

Fixes #20
---

diff --git a/src/config.rs b/src/config.rs
index 92d33c1..9741753 100644
--- a/src/config.rs
+++ b/src/config.rs
@@ -200,6 +200,13 @@ pub(crate) async fn upgrade_db(schema: i32, client: &mut tokio_postgres::Client)
 	if schema <= 1 || schema > SCHEMA_VERSION {
 		panic!("Unknown schema in db: {}, we support up to {}", schema, SCHEMA_VERSION);
 	}
+	// PostgreSQL (at least v13, but likely later versions as well) handles insert-only tables
+	// *very* poorly. After some number of inserts, it refuses to rely on indexes, assuming them to
+	// be possibly-stale, until a VACUUM happens. Thus, we set the vacuum factor really low here,
+	// pushing PostgreSQL to vacuum often.
+	// See https://www.cybertec-postgresql.com/en/postgresql-autovacuum-insert-only-tables/
+	let _ = client.execute("ALTER TABLE channel_updates SET ( autovacuum_vacuum_insert_scale_factor = 0.005 );", &[]).await;
+	let _ = client.execute("ALTER TABLE channel_announcements SET ( autovacuum_vacuum_insert_scale_factor = 0.005 );", &[]).await;
 }
 
 /// EDIT ME