--- /dev/null
+// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
+
+#ifndef STATCOLLECTORH
+#define STATCOLLECTORH
+
+#include <stdint.h>
+
+class StatCollector {
+public:
+ virtual uint64_t next_seq() = 0;
+ virtual void start_write(uint64_t seq, uint64_t size) = 0;
+ virtual void start_read(uint64_t seq, uint64_t size) = 0;
+ virtual void write_applied(uint64_t seq) = 0;
+ virtual void write_committed(uint64_t seq) = 0;
+ virtual void read_complete(uint64_t seq) = 0;
+ virtual ~StatCollector() {}
+};
+
+#endif