fix: fix comments

src/server/transaction.h

@@ -432,16 +432,17 @@ class Transaction {
   };
 
   // Barrier akin to helio's BlockingCounter, but with phase counting and proper acquire semantics
-  // for polling work from other threads. And without keap allocation.
-  struct PhasedBarrier {
+  // for polling work from other threads. And without heap allocation.
+  class PhasedBarrier {
+   public:
     uint32_t Start(uint32_t count);  // Release: Store count, return current phase
     bool Active() const;             // Acquire: Return if count > 0. Use for polling for work
 
     void Dec(Transaction* keep_alive);  // Relase: Decrease count, notify ec on 0
     void Wait();                        // Acquire: Wait until count = 0, increment phase
 
     bool IsMyPhase(uint32_t phase) const;  //  Return if same phase. Assumes called after Active().
-    uint32_t DEBUG_Get() const;
+    uint32_t DEBUG_Get() const;            // Get current counter value
 
    private:
     std::atomic_uint32_t phase_{0};
@@ -589,7 +590,7 @@ class Transaction {
   DbIndex db_index_{0};
   uint64_t time_now_ms_{0};
 
-  std::atomic_uint32_t use_count_{0};  // transaction exists only as a shared pointer (intrusive)
+  std::atomic_uint32_t use_count_{0};  // transaction exists only as an intrusive_ptr
 
   uint32_t unique_shard_cnt_{0};          // Number of unique shards active
   ShardId unique_shard_id_{kInvalidSid};  // Set if unique_shard_cnt_ = 1