From 6ba6652fcfe764341868638b9b0073500d00f69a Mon Sep 17 00:00:00 2001
From: John Sully <john@csquare.ca>
Date: Sun, 16 Aug 2020 00:26:05 +0000
Subject: [PATCH] Don't try and consolidate snapshots with a depth of 1

Former-commit-id: 26c298bd9bc4e2c6981de5c20284120ea54580c3
---
 src/server.h     | 3 +--
 src/snapshot.cpp | 4 ++--
 2 files changed, 3 insertions(+), 4 deletions(-)

diff --git a/src/server.h b/src/server.h
index a84368044..5c8c79a83 100644
--- a/src/server.h
+++ b/src/server.h
@@ -1421,13 +1421,12 @@ class redisDbPersistentDataSnapshot : protected redisDbPersistentData
 {
     friend class redisDbPersistentData;
 protected:
-    bool m_fConsolidated = false;
     static void gcDisposeSnapshot(redisDbPersistentDataSnapshot *psnapshot);
-    int snapshot_depth() const;
     void consolidate_children(redisDbPersistentData *pdbPrimary, bool fForce);
     bool freeTombstoneObjects(int depth);
 
 public:
+    int snapshot_depth() const;
     bool FWillFreeChildDebug() const { return m_spdbSnapshotHOLDER != nullptr; }
 
     bool iterate_threadsafe(std::function<bool(const char*, robj_roptr o)> fn, bool fKeyOnly = false, bool fCacheOnly = false) const;
diff --git a/src/snapshot.cpp b/src/snapshot.cpp
index a0187f1c5..c0ca378b1 100644
--- a/src/snapshot.cpp
+++ b/src/snapshot.cpp
@@ -571,11 +571,12 @@ void redisDbPersistentData::consolidate_snapshot()
 {
     aeAcquireLock();
     auto psnapshot = (m_pdbSnapshot != nullptr) ? m_spdbSnapshotHOLDER.get() : nullptr;
-    if (psnapshot == nullptr)
+    if (psnapshot == nullptr || psnapshot->snapshot_depth() == 0)
     {
         aeReleaseLock();
         return;
     }
+
     psnapshot->m_refCount++;    // ensure it's not free'd
     aeReleaseLock();
     psnapshot->consolidate_children(this, false /* fForce */);
@@ -648,7 +649,6 @@ void redisDbPersistentDataSnapshot::consolidate_children(redisDbPersistentData *
 
     serverLog(LL_VERBOSE, "cleaned %d snapshots", snapshot_depth()-1);
     spdb->m_refCount = depth;
-    spdb->m_fConsolidated = true;
     // Drop our refs from this snapshot and its children
     psnapshotT = this;
     std::vector<redisDbPersistentDataSnapshot*> vecT;