From 0d934d311ec81ca11cef1d5a93e47fa6adcf192d Mon Sep 17 00:00:00 2001
From: "Jeff Washington (jwash)"
 <75863576+jeffwashington@users.noreply.github.com>
Date: Mon, 18 Oct 2021 09:06:32 -0500
Subject: [PATCH] sort shrink acct indexes (#20708)

---
 runtime/src/accounts_db.rs | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/runtime/src/accounts_db.rs b/runtime/src/accounts_db.rs
index babb55cd00..dc243594af 100644
--- a/runtime/src/accounts_db.rs
+++ b/runtime/src/accounts_db.rs
@@ -2471,7 +2471,7 @@ impl AccountsDb {
         unrefed_pubkeys: &mut Vec<&'a Pubkey>,
     ) -> usize
     where
-        I: Iterator<Item = (&'a Pubkey, &'a FoundStoredAccount<'a>)>,
+        I: Iterator<Item = &'a (Pubkey, FoundStoredAccount<'a>)>,
     {
         let mut alive_total = 0;
 
@@ -2544,6 +2544,10 @@ impl AccountsDb {
             num_stores += 1;
         }
 
+        // sort by pubkey to keep account index lookups close
+        let mut stored_accounts = stored_accounts.into_iter().collect::<Vec<_>>();
+        stored_accounts.sort_unstable_by(|a, b| a.0.cmp(&b.0));
+
         let mut index_read_elapsed = Measure::start("index_read_elapsed");
         let alive_total_collect = AtomicUsize::new(0);