From 3f47b85e3b0ebd29c76934be3313d91718fe5973 Mon Sep 17 00:00:00 2001
From: Nathan Nichols <natenichols@cox.net>
Date: Sun, 15 May 2022 19:29:05 -0500
Subject: [PATCH] disable cache when CacheLoadStyle::NONE (#152)

---
 src/backend/SimpleCache.cpp | 13 +++++++++++++
 src/backend/SimpleCache.h   |  4 ++++
 src/etl/ReportingETL.cpp    |  1 +
 3 files changed, 18 insertions(+)

diff --git a/src/backend/SimpleCache.cpp b/src/backend/SimpleCache.cpp
index 6defa5bc..01c46572 100644
--- a/src/backend/SimpleCache.cpp
+++ b/src/backend/SimpleCache.cpp
@@ -1,5 +1,6 @@
 #include <backend/SimpleCache.h>
 namespace Backend {
+
 uint32_t
 SimpleCache::latestLedgerSequence() const
 {
@@ -13,6 +14,9 @@ SimpleCache::update(
     uint32_t seq,
     bool isBackground)
 {
+    if (disabled_)
+        return;
+
     {
         std::unique_lock lck{mtx_};
         if (seq > latestSeq_)
@@ -82,9 +86,18 @@ SimpleCache::get(ripple::uint256 const& key, uint32_t seq) const
     return {e->second.blob};
 }
 
+void
+SimpleCache::setDisabled()
+{
+    disabled_ = true;
+}
+
 void
 SimpleCache::setFull()
 {
+    if (disabled_)
+        return;
+
     full_ = true;
     std::unique_lock lck{mtx_};
     deletes_.clear();
diff --git a/src/backend/SimpleCache.h b/src/backend/SimpleCache.h
index 4cabd0e7..db78d7f8 100644
--- a/src/backend/SimpleCache.h
+++ b/src/backend/SimpleCache.h
@@ -21,6 +21,7 @@ class SimpleCache
     mutable std::shared_mutex mtx_;
     uint32_t latestSeq_ = 0;
     std::atomic_bool full_ = false;
+    std::atomic_bool disabled_ = false;
     // temporary set to prevent background thread from writing already deleted
     // data. not used when cache is full
     std::unordered_set<ripple::uint256, ripple::hardened_hash<>> deletes_;
@@ -45,6 +46,9 @@ public:
     std::optional<LedgerObject>
     getPredecessor(ripple::uint256 const& key, uint32_t seq) const;
 
+    void
+    setDisabled();
+
     void
     setFull();
 
diff --git a/src/etl/ReportingETL.cpp b/src/etl/ReportingETL.cpp
index ab2a04f1..28f4ece2 100644
--- a/src/etl/ReportingETL.cpp
+++ b/src/etl/ReportingETL.cpp
@@ -894,6 +894,7 @@ ReportingETL::loadCache(uint32_t seq)
 {
     if (cacheLoadStyle_ == CacheLoadStyle::NOT_AT_ALL)
     {
+        backend_->cache().setDisabled();
         BOOST_LOG_TRIVIAL(warning) << "Cache is disabled. Not loading";
         return;
     }