add call chain for defragmenting indices

Signed-off-by: Abhijat Malviya <[email protected]>

Author: abhijat

src/server/search/doc_index.cc

@@ -829,4 +829,26 @@ SearchStats ShardDocIndices::GetStats() const {
   return {GetUsedMemory(), indices_.size(), total_entries};
 }
 
+ssize_t ShardDocIndices::Defragment(PageUsage* page_usage, ssize_t quota) {
+  auto it = next_defrag_index_.empty() ? indices_.end() : indices_.find(next_defrag_index_);
+  if (it == indices_.end()) {
+    it = indices_.begin();
+  }
+
+  for (; it != indices_.end() && quota > 0; ++it) {
+    auto& [name, index] = *it;
+    quota = index->Defragment(page_usage, quota);
+    if (quota == 0) {
+      next_defrag_index_ = name;
+      break;
+    }
+  }
+
+  if (it == indices_.end()) {
+    next_defrag_index_.clear();
+  }
+
+  return quota;
+}
+
 }  // namespace dfly

src/server/search/doc_index.h

@@ -306,6 +306,13 @@ class ShardDocIndex {
       search::DocId id, const OpArgs& op_args, const search::Schema& schema,
       const std::optional<std::vector<FieldReference>>& return_fields);
 
+  ssize_t Defragment(PageUsage* page_usage, ssize_t quota) {
+    if (indices_) {
+      return indices_->Defragment(page_usage, quota);
+    }
+    return quota;
+  }
+
  private:
   // Clears internal data. Traverses all matching documents and assigns ids.
   void Rebuild(const OpArgs& op_args, PMR_NS::memory_resource* mr);
@@ -355,13 +362,18 @@ class ShardDocIndices {
 
   size_t GetUsedMemory() const;
   SearchStats GetStats() const;  // combines stats for all indices
+
+  ssize_t Defragment(PageUsage* page_usage, ssize_t quota);
+
  private:
   // Clean caches that might have data from this index
   void DropIndexCache(const dfly::ShardDocIndex& shard_doc_index);
 
  private:
   MiMemoryResource local_mr_;
   absl::flat_hash_map<std::string, std::unique_ptr<ShardDocIndex>> indices_;
+
+  std::string next_defrag_index_;
 };
 
 }  // namespace dfly