add ChainstateManager::MaybeRebalanceCaches()

Aside from in unittests, this method is unused at the moment. It will be used
in upcoming commits that enable utxo snapshot activation.

1 files changed, 30 insertions, 0 deletions

diff --git a/src/validation.cpp b/src/validation.cpp
index 1d7d85b751..906ed943b2 100644
--- a/src/validation.cpp
+++ b/src/validation.cpp
@@ -5297,3 +5297,33 @@ void ChainstateManager::Reset()
     m_active_chainstate = nullptr;
     m_snapshot_validated = false;
 }
+
+void ChainstateManager::MaybeRebalanceCaches()
+{
+    if (m_ibd_chainstate && !m_snapshot_chainstate) {
+        LogPrintf("[snapshot] allocating all cache to the IBD chainstate\n");
+        // Allocate everything to the IBD chainstate.
+        m_ibd_chainstate->ResizeCoinsCaches(m_total_coinstip_cache, m_total_coinsdb_cache);
+    }
+    else if (m_snapshot_chainstate && !m_ibd_chainstate) {
+        LogPrintf("[snapshot] allocating all cache to the snapshot chainstate\n");
+        // Allocate everything to the snapshot chainstate.
+        m_snapshot_chainstate->ResizeCoinsCaches(m_total_coinstip_cache, m_total_coinsdb_cache);
+    }
+    else if (m_ibd_chainstate && m_snapshot_chainstate) {
+        // If both chainstates exist, determine who needs more cache based on IBD status.
+        //
+        // Note: shrink caches first so that we don't inadvertently overwhelm available memory.
+        if (m_snapshot_chainstate->IsInitialBlockDownload()) {
+            m_ibd_chainstate->ResizeCoinsCaches(
+                m_total_coinstip_cache * 0.05, m_total_coinsdb_cache * 0.05);
+            m_snapshot_chainstate->ResizeCoinsCaches(
+                m_total_coinstip_cache * 0.95, m_total_coinsdb_cache * 0.95);
+        } else {
+            m_snapshot_chainstate->ResizeCoinsCaches(
+                m_total_coinstip_cache * 0.05, m_total_coinsdb_cache * 0.05);
+            m_ibd_chainstate->ResizeCoinsCaches(
+                m_total_coinstip_cache * 0.95, m_total_coinsdb_cache * 0.95);
+        }
+    }
+}