From 5a8f2dd961599b804c9ec31d51f36464735aef03 Mon Sep 17 00:00:00 2001
From: Michael Sproul <michael@sigmaprime.io>
Date: Fri, 10 Jan 2020 14:42:49 +1100
Subject: [PATCH] Increase default slots per restore point to 2048 (#790)

This should reduce disk usage by 32x while keeping historical state queries to
less than 10s. If historical states are required quickly, the minimum SPRP of 32
can be set on the CLI.
---
 beacon_node/src/cli.rs          | 9 +--------
 beacon_node/src/config.rs       | 5 +++++
 beacon_node/store/src/config.rs | 4 ++++
 3 files changed, 10 insertions(+), 8 deletions(-)

diff --git a/beacon_node/src/cli.rs b/beacon_node/src/cli.rs
index bf40b83b5d..bdd4a1b1a2 100644
--- a/beacon_node/src/cli.rs
+++ b/beacon_node/src/cli.rs
@@ -1,5 +1,4 @@
 use clap::{App, Arg, SubCommand};
-use store::StoreConfig;
 
 pub fn cli_app<'a, 'b>() -> App<'a, 'b> {
     App::new("beacon_node")
@@ -196,14 +195,8 @@ pub fn cli_app<'a, 'b>() -> App<'a, 'b> {
                 .long("slots-per-restore-point")
                 .value_name("SLOT_COUNT")
                 .help("Specifies how often a freezer DB restore point should be stored. \
-                       DO NOT CHANGE AFTER INITIALIZATION.")
+                       DO NOT DECREASE AFTER INITIALIZATION. [default: 2048 (mainnet) or 64 (minimal)]")
                 .takes_value(true)
-                .default_value(
-                    Box::leak(
-                        format!("{}", StoreConfig::default().slots_per_restore_point)
-                            .into_boxed_str()
-                    )
-                )
         )
         /*
          * The "testnet" sub-command.
diff --git a/beacon_node/src/config.rs b/beacon_node/src/config.rs
index 6b9490a29a..61d6f7db36 100644
--- a/beacon_node/src/config.rs
+++ b/beacon_node/src/config.rs
@@ -258,6 +258,11 @@ pub fn get_configs<E: EthSpec>(
         client_config.store.slots_per_restore_point = slots_per_restore_point
             .parse()
             .map_err(|_| "slots-per-restore-point is not a valid integer".to_string())?;
+    } else {
+        client_config.store.slots_per_restore_point = std::cmp::min(
+            E::slots_per_historical_root() as u64,
+            store::config::DEFAULT_SLOTS_PER_RESTORE_POINT,
+        );
     }
 
     if eth2_config.spec_constants != client_config.spec_constants {
diff --git a/beacon_node/store/src/config.rs b/beacon_node/store/src/config.rs
index 4693942eb9..36e2934a4a 100644
--- a/beacon_node/store/src/config.rs
+++ b/beacon_node/store/src/config.rs
@@ -5,6 +5,9 @@ use types::{EthSpec, MinimalEthSpec};
 /// Default directory name for the freezer database under the top-level data dir.
 const DEFAULT_FREEZER_DB_DIR: &str = "freezer_db";
 
+/// Default value for the freezer DB's restore point frequency.
+pub const DEFAULT_SLOTS_PER_RESTORE_POINT: u64 = 2048;
+
 #[derive(Debug, Clone, Serialize, Deserialize)]
 pub struct StoreConfig {
     /// Name of the directory inside the data directory where the main "hot" DB is located.
@@ -20,6 +23,7 @@ impl Default for StoreConfig {
         Self {
             db_name: "chain_db".to_string(),
             freezer_db_path: None,
+            // Safe default for tests, shouldn't ever be read by a CLI node.
             slots_per_restore_point: MinimalEthSpec::slots_per_historical_root() as u64,
         }
     }