From 8489ee7df9614073ab042a1c5b08ddc26041f139 Mon Sep 17 00:00:00 2001
From: "Jeff Washington (jwash)"
 <75863576+jeffwashington@users.noreply.github.com>
Date: Wed, 8 Sep 2021 21:27:08 -0500
Subject: [PATCH] Revert "collect rent in parallel for partitions (#19478)"
 (#19723)

This reverts commit 1560d5e3c389191de175f438e72958895fb68b8e.
---
 runtime/src/bank.rs | 15 ++++-----------
 1 file changed, 4 insertions(+), 11 deletions(-)

diff --git a/runtime/src/bank.rs b/runtime/src/bank.rs
index 5979f3604c..310fabb99a 100644
--- a/runtime/src/bank.rs
+++ b/runtime/src/bank.rs
@@ -65,10 +65,7 @@ use crate::{
 use byteorder::{ByteOrder, LittleEndian};
 use itertools::Itertools;
 use log::*;
-use rayon::{
-    iter::{IntoParallelIterator, ParallelIterator},
-    ThreadPool,
-};
+use rayon::ThreadPool;
 use solana_measure::measure::Measure;
 use solana_metrics::{datapoint_debug, inc_new_counter_debug, inc_new_counter_info};
 use solana_program_runtime::{ExecuteDetailsTimings, Executors};
@@ -3867,13 +3864,9 @@ impl Bank {
         }
 
         let mut measure = Measure::start("collect_rent_eagerly-ms");
-        self.rc.accounts.accounts_db.thread_pool.install(|| {
-            self.rent_collection_partitions()
-                .into_par_iter()
-                .for_each(|partition| {
-                    self.collect_rent_in_partition(partition);
-                });
-        });
+        for partition in self.rent_collection_partitions() {
+            self.collect_rent_in_partition(partition);
+        }
         measure.stop();
         inc_new_counter_info!("collect_rent_eagerly-ms", measure.as_ms() as usize);
     }