From 51c0649af8cce3066e499cab1a47a8d1be6c6e6c Mon Sep 17 00:00:00 2001
From: Yueh-Hsuan Chiang <93241502+yhchiang-sol@users.noreply.github.com>
Date: Thu, 25 Jan 2024 17:17:24 -0800
Subject: [PATCH] [TieredStorage] Use RENT_EXEMPT_RENT_EPOCH in
 HotStorageWriter (#34950)

#### Problem
In HotStorageWriter::write_accounts, it skips storing rent-epoch when
the rent-epoch equals Epoch::MAX.  While the value is correct, it is
more suitable to use RENT_EXEMPT_RENT_EPOCH instead as the
goal here is to save bytes for rent-exempt accounts.

#### Summary of Changes
Replace Epoch::MAX by RENT_EXEMPT_RENT_EPOCH when checking
whether to skip storing rent-epoch in HotStorageWriter.
---
 accounts-db/src/tiered_storage/hot.rs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/accounts-db/src/tiered_storage/hot.rs b/accounts-db/src/tiered_storage/hot.rs
index 8652b0b2aa..f87b1c2c25 100644
--- a/accounts-db/src/tiered_storage/hot.rs
+++ b/accounts-db/src/tiered_storage/hot.rs
@@ -5,6 +5,7 @@ use {
         account_storage::meta::StoredAccountMeta,
         accounts_file::MatchAccountOwnerError,
         accounts_hash::AccountHash,
+        rent_collector::RENT_EXEMPT_RENT_EPOCH,
         tiered_storage::{
             byte_block,
             file::TieredStorageFile,
@@ -562,7 +563,7 @@ impl HotStorageWriter {
                         acc.data(),
                         acc.executable(),
                         // only persist rent_epoch for those non-rent-exempt accounts
-                        (acc.rent_epoch() != Epoch::MAX).then_some(acc.rent_epoch()),
+                        (acc.rent_epoch() != RENT_EXEMPT_RENT_EPOCH).then_some(acc.rent_epoch()),
                         Some(*account_hash),
                     )
                 })
@@ -606,7 +607,6 @@ pub mod tests {
         super::*,
         crate::{
             account_storage::meta::StoredMeta,
-            rent_collector::RENT_EXEMPT_RENT_EPOCH,
             tiered_storage::{
                 byte_block::ByteBlockWriter,
                 file::TieredStorageFile,