From cbcd3ef27e61f323f9d532e6dbb543246fcaf1bc Mon Sep 17 00:00:00 2001
From: Tao Zhu <82401714+taozhu-chicago@users.noreply.github.com>
Date: Fri, 24 Feb 2023 23:50:02 -0600
Subject: [PATCH] Not allow transactions request zero CU to update
 prioritization fee cache (#30507)

* filter out transaction requests zero cu from updating prioritization fee cache

* updated comment
---
 runtime/src/prioritization_fee_cache.rs | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/runtime/src/prioritization_fee_cache.rs b/runtime/src/prioritization_fee_cache.rs
index aa0017ec2c..7df9c18078 100644
--- a/runtime/src/prioritization_fee_cache.rs
+++ b/runtime/src/prioritization_fee_cache.rs
@@ -219,6 +219,13 @@ impl PrioritizationFeeCache {
                     if priority_details.is_none() || account_locks.is_err() {
                         continue;
                     }
+                    let priority_details = priority_details.unwrap();
+
+                    // filter out any transaction that requests zero compute_unit_limit
+                    // since its priority fee amount is not instructive
+                    if priority_details.compute_unit_limit == 0 {
+                        continue;
+                    }
 
                     let writable_accounts = Arc::new(
                         account_locks
@@ -232,7 +239,7 @@ impl PrioritizationFeeCache {
                     self.sender
                         .send(CacheServiceUpdate::TransactionUpdate {
                             slot: bank.slot(),
-                            transaction_fee: priority_details.unwrap().priority,
+                            transaction_fee: priority_details.priority,
                             writable_accounts,
                         })
                         .unwrap_or_else(|err| {