From 631f051c681b70debd59a78a05c923a0d9e9fff5 Mon Sep 17 00:00:00 2001
From: sakridge <sakridge@gmail.com>
Date: Fri, 10 Jul 2020 11:54:45 -0700
Subject: [PATCH] Add jitter to cleanup to prevent all nodes cleaning at the
 same time (#10936)

---
 core/src/accounts_background_service.rs | 5 ++++-
 runtime/src/accounts_db.rs              | 4 ++--
 2 files changed, 6 insertions(+), 3 deletions(-)

diff --git a/core/src/accounts_background_service.rs b/core/src/accounts_background_service.rs
index 030bdb3ff3..92c052c75d 100644
--- a/core/src/accounts_background_service.rs
+++ b/core/src/accounts_background_service.rs
@@ -2,6 +2,7 @@
 //
 // This can be expensive since we have to walk the append vecs being cleaned up.
 
+use rand::{thread_rng, Rng};
 use solana_runtime::bank_forks::BankForks;
 use std::sync::{
     atomic::{AtomicBool, Ordering},
@@ -39,7 +40,9 @@ impl AccountsBackgroundService {
                 consumed_budget = bank
                     .process_stale_slot_with_budget(consumed_budget, SHRUNKEN_ACCOUNT_PER_INTERVAL);
 
-                if bank.block_height() - last_cleaned_slot > CLEAN_INTERVAL_SLOTS {
+                if bank.block_height() - last_cleaned_slot
+                    > (CLEAN_INTERVAL_SLOTS + thread_rng().gen_range(0, 10))
+                {
                     bank.clean_accounts();
                     last_cleaned_slot = bank.block_height();
                 }
diff --git a/runtime/src/accounts_db.rs b/runtime/src/accounts_db.rs
index b24169d2d5..dc394679ae 100644
--- a/runtime/src/accounts_db.rs
+++ b/runtime/src/accounts_db.rs
@@ -721,7 +721,7 @@ impl AccountsDB {
 
         let mut reclaims_time = Measure::start("reclaims");
         // Recalculate reclaims with new purge set
-        let purges_key_to_slot_set: Vec<_> = purges
+        let pubkey_to_slot_set: Vec<_> = purges
             .into_iter()
             .map(|(key, (slots_list, _ref_count))| {
                 (
@@ -733,7 +733,7 @@ impl AccountsDB {
         let accounts_index = self.accounts_index.read().unwrap();
         let mut reclaims = Vec::new();
         let mut dead_keys = Vec::new();
-        for (pubkey, slots_set) in purges_key_to_slot_set {
+        for (pubkey, slots_set) in pubkey_to_slot_set {
             let (new_reclaims, is_empty) = accounts_index.purge_exact(&pubkey, slots_set);
             if is_empty {
                 dead_keys.push(pubkey);