cache reference tracking (#455)

- Feature: Add caching of referenced CId content for structured cache records, this avoid disk thrashing when gathering references for GC
  - disabled by default, enable with `--cache-reference-cache-enabled`
- Improvement: Faster collection of referenced CId content in project store

1 files changed, 9 insertions, 6 deletions

diff --git a/src/zenserver/projectstore/projectstore.cpp b/src/zenserver/projectstore/projectstore.cpp
index e000976ea..02760f6dd 100644
--- a/src/zenserver/projectstore/projectstore.cpp
+++ b/src/zenserver/projectstore/projectstore.cpp
@@ -507,14 +507,17 @@ ProjectStore::Oplog::GatherReferences(GcContext& GcCtx)
 		return;
 	}
 
-	tsl::robin_set<IoHash> AttachmentHashes;
+	std::vector<IoHash> Cids;
+	Cids.reserve(1024);
 	IterateOplog([&](CbObject Op) {
-		Op.IterateAttachments([&](CbFieldView Visitor) {
-			IoHash Attachment = Visitor.AsAttachment();
-			AttachmentHashes.insert(Attachment);
-		});
+		Op.IterateAttachments([&](CbFieldView Visitor) { Cids.emplace_back(Visitor.AsAttachment()); });
+		if (Cids.size() >= 1024)
+		{
+			GcCtx.AddRetainedCids(Cids);
+			Cids.clear();
+		}
 	});
-	GcCtx.AddRetainedCids(std::vector<IoHash>(AttachmentHashes.begin(), AttachmentHashes.end()));
+	GcCtx.AddRetainedCids(Cids);
 }
 
 uint64_t