Bug#58052 Binary log IO not being accounted for properly

Before this fix, file io for the binary log file was not accounted properly,
and showed no io at all.

This bug was due to the following issues:

1) file io for the binlog was instrumented:
- sometime as "wait/io/file/sql/binlog"
- sometime as "wait/io/file/sql/MYSQL_LOG"
leading to inconsistent event_names.

2) the binlog file itself was using an IO_CACHE,
but the IO_CACHE implementation in mysys/mf_iocache.c was
not instrumented to make performance schema calls to record file io.

3) The "wait/io/file/sql/MYSQL_LOG" instrumentation was used
for several log files, such as:
- the binary log
- the slow log
- the query log
which caused file io in these different log files to be accounted
against the same instrument.
The instrumentation needs to have a finer grain and report io
in different event_names, because each file really serves a different purpose.

With this fix:
- the IO_CACHE implementation is now instrumented
- the "wait/io/file/sql/MYSQL_LOG" instrument has been removed
- binlog io is now always instrumented with "wait/io/file/sql/binlog"
- the slow log is instrumented with a new name, "wait/io/file/sql/slow_log"
- the query log is instrumented with a new name, "wait/io/file/sql/query_log"

1 files changed, 21 insertions, 5 deletions

diff --git a/sql/log.h b/sql/log.h
index 89b3594cd1e..d824d3afa26 100644
--- a/sql/log.h
+++ b/sql/log.h
@@ -196,7 +196,11 @@ public:
   MYSQL_LOG();
   void init_pthread_objects();
   void cleanup();
-  bool open(const char *log_name,
+  bool open(
+#ifdef HAVE_PSI_INTERFACE
+            PSI_file_key log_file_key,
+#endif
+            const char *log_name,
             enum_log_type log_type,
             const char *new_name,
             enum cache_type io_cache_type_arg);
@@ -223,6 +227,10 @@ public:
   volatile enum_log_state log_state;
   enum cache_type io_cache_type;
   friend class Log_event;
+#ifdef HAVE_PSI_INTERFACE
+  /** Instrumentation key to use for file io in @c log_file */
+  PSI_file_key m_log_file_key;
+#endif
 };
 
 class MYSQL_QUERY_LOG: public MYSQL_LOG
@@ -241,14 +249,22 @@ public:
   bool open_slow_log(const char *log_name)
   {
     char buf[FN_REFLEN];
-    return open(generate_name(log_name, "-slow.log", 0, buf), LOG_NORMAL, 0,
-                WRITE_CACHE);
+    return open(
+#ifdef HAVE_PSI_INTERFACE
+                key_file_slow_log,
+#endif
+                generate_name(log_name, "-slow.log", 0, buf),
+                LOG_NORMAL, 0, WRITE_CACHE);
   }
   bool open_query_log(const char *log_name)
   {
     char buf[FN_REFLEN];
-    return open(generate_name(log_name, ".log", 0, buf), LOG_NORMAL, 0,
-                WRITE_CACHE);
+    return open(
+#ifdef HAVE_PSI_INTERFACE
+                key_file_query_log,
+#endif
+                generate_name(log_name, ".log", 0, buf),
+                LOG_NORMAL, 0, WRITE_CACHE);
   }
 
 private: