Port v5.1: JEMalloc Stats

Summary:
This ports our support for jemalloc stats info in mysqld (only).

Update jemalloc stats only when needed

Reference Patch: 942ff23

Reviewed By: lth

Differential Revision: D7337802

fbshipit-source-id: 2b13933

Author: steaphangreene

include/my_sqlcommand.h

@@ -203,6 +203,7 @@ enum enum_sql_command {
   SQLCOM_CREATE_SRS,
   SQLCOM_DROP_SRS,
   SQLCOM_SHOW_ENGINE_TRX,
+  SQLCOM_SHOW_MEMORY_STATUS,
   /* This should be the last !!! */
   SQLCOM_END
 };

include/mysql/plugin_audit.h.pp

@@ -335,6 +335,7 @@
   SQLCOM_CREATE_SRS,
   SQLCOM_DROP_SRS,
   SQLCOM_SHOW_ENGINE_TRX,
+  SQLCOM_SHOW_MEMORY_STATUS,
   SQLCOM_END
 };
 #include "plugin_audit_message_types.h"

mysql-test/include/have_jemalloc.inc

@@ -0,0 +1,5 @@
+# Skip test if build didn't specify -DHAVE_JEMALLOC
+if (`SELECT COUNT(*) = 0 FROM performance_schema.global_status WHERE VARIABLE_NAME LIKE "Jemalloc%"`)
+{
+  --skip Test requires jemalloc
+}

mysql-test/r/jemalloc.result

@@ -0,0 +1,8 @@
+select variable_name from performance_schema.global_status where variable_name like "Jemalloc%" order by 1;
+variable_name
+Jemalloc_arenas_narenas
+Jemalloc_opt_narenas
+Jemalloc_opt_tcache
+Jemalloc_stats_active
+Jemalloc_stats_allocated
+Jemalloc_stats_mapped

mysql-test/r/mysqld--help-notwin.result

@@ -1671,7 +1671,7 @@ performance-schema-max-socket-classes 10
 performance-schema-max-socket-instances -1
 performance-schema-max-sql-text-length 1024
 performance-schema-max-stage-classes 175
-performance-schema-max-statement-classes 219
+performance-schema-max-statement-classes 220
 performance-schema-max-statement-stack 10
 performance-schema-max-table-handles -1
 performance-schema-max-table-instances -1

mysql-test/t/jemalloc.test

@@ -0,0 +1,3 @@
+--source include/have_jemalloc.inc
+
+select variable_name from performance_schema.global_status where variable_name like "Jemalloc%" order by 1;

sql/mysqld.cc

@@ -790,6 +790,10 @@ The documentation is based on the source files such as:
 #include "sql/dd/upgrade_57/upgrade.h"  // dd::upgrade_57::in_progress
 #include "sql/srv_session.h"
 
+#ifdef HAVE_JEMALLOC
+#include <jemalloc/jemalloc.h>
+#endif
+
 using std::max;
 using std::min;
 using std::vector;
@@ -4040,6 +4044,10 @@ SHOW_VAR com_status_vars[] = {
      (char *)offsetof(System_status_var,
                       com_stat[(uint)SQLCOM_SHOW_MASTER_STAT]),
      SHOW_LONG_STATUS, SHOW_SCOPE_ALL},
+    {"show_memory_status",
+     (char *)offsetof(System_status_var,
+                      com_stat[(uint)SQLCOM_SHOW_MEMORY_STATUS]),
+     SHOW_LONG_STATUS, SHOW_SCOPE_ALL},
     {"show_open_tables",
      (char *)offsetof(System_status_var,
                       com_stat[(uint)SQLCOM_SHOW_OPEN_TABLES]),
@@ -7985,6 +7993,107 @@ struct my_option my_long_options[] = {
 
     {0, 0, 0, 0, 0, 0, GET_NO_ARG, NO_ARG, 0, 0, 0, 0, 0, 0}};
 
+#ifdef HAVE_JEMALLOC
+#ifndef EMBEDDED_LIBRARY
+std::atomic_bool need_update_malloc_status;
+
+static void update_malloc_status() {
+  if (!need_update_malloc_status) return;
+
+  uint64_t val = 1;
+  size_t len = sizeof(val);
+
+  mallctl("epoch", &val, &len, &val, sizeof(uint64_t));
+  need_update_malloc_status = false;
+}
+
+static int show_jemalloc_sizet(THD *thd MY_ATTRIBUTE((unused)), SHOW_VAR *var,
+                               char *buff, const char *stat_name) {
+  size_t len, val;
+  len = sizeof(val);
+
+  var->type = SHOW_LONGLONG;
+  var->value = buff;
+
+  if (!mallctl(stat_name, &val, &len, NULL, 0)) {
+    *((ulonglong *)buff) = (ulonglong)val;
+  } else {
+    *((ulonglong *)buff) = 0;
+  }
+
+  /* Always return 0 to avoid worrying about error handling */
+  return 0;
+}
+
+static int show_jemalloc_unsigned(THD *thd MY_ATTRIBUTE((unused)),
+                                  SHOW_VAR *var, char *buff,
+                                  const char *stat_name) {
+  unsigned val;
+  size_t len = sizeof(val);
+
+  var->type = SHOW_LONG;
+  var->value = buff;
+
+  if (!mallctl(stat_name, &val, &len, NULL, 0)) {
+    *((ulong *)buff) = (ulong)val;
+  } else {
+    *((ulong *)buff) = 0;
+  }
+
+  /* Always return 0 to avoid worrying about error handling */
+  return 0;
+}
+
+static int show_jemalloc_bool(THD *thd MY_ATTRIBUTE((unused)), SHOW_VAR *var,
+                              char *buff, const char *stat_name) {
+  bool val;
+  size_t len = sizeof(val);
+
+  var->type = SHOW_LONG;
+  var->value = buff;
+
+  if (!mallctl(stat_name, &val, &len, NULL, 0)) {
+    *((ulong *)buff) = (ulong)val;
+  } else {
+    *((ulong *)buff) = 0;
+  }
+
+  /* Always return 0 to avoid worrying about error handling */
+  return 0;
+}
+
+static int show_jemalloc_arenas_narenas(THD *thd, SHOW_VAR *var, char *buff) {
+  update_malloc_status();
+  return show_jemalloc_unsigned(thd, var, buff, "arenas.narenas");
+}
+
+static int show_jemalloc_opt_narenas(THD *thd, SHOW_VAR *var, char *buff) {
+  update_malloc_status();
+  return show_jemalloc_sizet(thd, var, buff, "opt.narenas");
+}
+
+static int show_jemalloc_opt_tcache(THD *thd, SHOW_VAR *var, char *buff) {
+  update_malloc_status();
+  return show_jemalloc_bool(thd, var, buff, "opt.tcache");
+}
+
+static int show_jemalloc_active(THD *thd, SHOW_VAR *var, char *buff) {
+  update_malloc_status();
+  return show_jemalloc_sizet(thd, var, buff, "stats.active");
+}
+
+static int show_jemalloc_allocated(THD *thd, SHOW_VAR *var, char *buff) {
+  update_malloc_status();
+  return show_jemalloc_sizet(thd, var, buff, "stats.allocated");
+}
+
+static int show_jemalloc_mapped(THD *thd, SHOW_VAR *var, char *buff) {
+  update_malloc_status();
+  return show_jemalloc_sizet(thd, var, buff, "stats.mapped");
+}
+#endif /* EMBEDDED_LIBRARY */
+#endif /* HAVE_JEMALLOC */
+
 static int show_queries(THD *thd, SHOW_VAR *var, char *) {
   var->type = SHOW_LONGLONG;
   var->value = (char *)&thd->query_id;
@@ -8507,6 +8616,20 @@ SHOW_VAR status_vars[] = {
      SHOW_LONGLONG_STATUS, SHOW_SCOPE_ALL},
     {"Handler_write", (char *)offsetof(System_status_var, ha_write_count),
      SHOW_LONGLONG_STATUS, SHOW_SCOPE_ALL},
+#ifdef HAVE_JEMALLOC
+    {"Jemalloc_arenas_narenas", (char *)&show_jemalloc_arenas_narenas,
+     SHOW_FUNC, SHOW_SCOPE_ALL},
+    {"Jemalloc_opt_narenas", (char *)&show_jemalloc_opt_narenas, SHOW_FUNC,
+     SHOW_SCOPE_ALL},
+    {"Jemalloc_opt_tcache", (char *)&show_jemalloc_opt_tcache, SHOW_FUNC,
+     SHOW_SCOPE_ALL},
+    {"Jemalloc_stats_active", (char *)&show_jemalloc_active, SHOW_FUNC,
+     SHOW_SCOPE_ALL},
+    {"Jemalloc_stats_allocated", (char *)&show_jemalloc_allocated, SHOW_FUNC,
+     SHOW_SCOPE_ALL},
+    {"Jemalloc_stats_mapped", (char *)&show_jemalloc_mapped, SHOW_FUNC,
+     SHOW_SCOPE_ALL},
+#endif
     {"Key_blocks_not_flushed",
      (char *)offsetof(KEY_CACHE, global_blocks_changed), SHOW_KEY_CACHE_LONG,
      SHOW_SCOPE_GLOBAL},

sql/sp.cc

@@ -2270,6 +2270,7 @@ uint sp_get_flags_for_command(LEX *lex) {
     case SQLCOM_SHOW_EVENTS:
     case SQLCOM_SHOW_KEYS:
     case SQLCOM_SHOW_MASTER_STAT:
+    case SQLCOM_SHOW_MEMORY_STATUS:
     case SQLCOM_SHOW_OPEN_TABLES:
     case SQLCOM_SHOW_PRIVILEGES:
     case SQLCOM_SHOW_PROCESSLIST:

sql/sql_parse.cc

@@ -24,6 +24,10 @@
 
 #include "my_config.h"
 
+#ifdef HAVE_JEMALLOC
+#include "jemalloc/jemalloc.h"
+#endif
+
 #include <limits.h>
 #include <stdio.h>
 #include <stdlib.h>
@@ -546,6 +550,7 @@ void init_sql_command_flags(void) {
   sql_command_flags[SQLCOM_SHOW_CREATE_DB] = CF_STATUS_COMMAND;
   sql_command_flags[SQLCOM_SHOW_CREATE] = CF_STATUS_COMMAND;
   sql_command_flags[SQLCOM_SHOW_MASTER_STAT] = CF_STATUS_COMMAND;
+  sql_command_flags[SQLCOM_SHOW_MEMORY_STATUS] = CF_STATUS_COMMAND;
   sql_command_flags[SQLCOM_SHOW_SLAVE_STAT] = CF_STATUS_COMMAND;
   sql_command_flags[SQLCOM_SHOW_CREATE_PROC] = CF_STATUS_COMMAND;
   sql_command_flags[SQLCOM_SHOW_CREATE_FUNC] = CF_STATUS_COMMAND;
@@ -2564,6 +2569,69 @@ static bool lock_tables_open_and_lock_tables(THD *thd, TABLE_LIST *tables) {
   return true;
 }
 
+typedef struct {
+  char *cur;
+  char *end;
+} malloc_status;
+
+#ifdef HAVE_JEMALLOC
+static void get_jemalloc_status(void *mstat_arg, const char *status) {
+  malloc_status *mstat = (malloc_status *)mstat_arg;
+  size_t status_len = status ? strlen(status) : 0;
+
+  if (!status_len || status_len > (size_t)(mstat->end - mstat->cur)) return;
+
+  strcpy(mstat->cur, status);
+  mstat->cur += status_len;
+}
+#endif
+
+static int show_memory_status(THD *thd) {
+  List<Item> field_list;
+  Protocol *protocol = thd->get_protocol();
+  malloc_status mstat;
+  char *buf;
+  /*
+    Buffer size in bytes. Should be large enough for per-arena statistics not
+    to be truncated.
+  */
+  const uint MALLOC_STATUS_LEN = 1000000;
+
+  field_list.push_back(new Item_empty_string("Status", 10));
+  if (thd->send_result_metadata(&field_list,
+                                Protocol::SEND_NUM_ROWS | Protocol::SEND_EOF))
+    return true;
+
+  protocol->start_row();
+
+  buf = (char *)my_malloc(PSI_NOT_INSTRUMENTED, MALLOC_STATUS_LEN + 1, MYF(0));
+  mstat.cur = buf;
+  mstat.end = buf + MALLOC_STATUS_LEN;
+  if (!buf) return true;
+
+#ifdef HAVE_JEMALLOC
+  /*
+    get_jemalloc_status will be called many times per call to
+    malloc_stats_print.
+  */
+  malloc_stats_print(get_jemalloc_status, &mstat, "");
+#else
+  strcpy(buf, "You should be using jemalloc");
+  mstat.cur += strlen(buf);
+#endif
+
+  protocol->store(buf, mstat.cur - buf, system_charset_info);
+  if (protocol->end_row()) {
+    my_free((void *)buf);
+    return true;
+  }
+
+  my_free((void *)buf);
+
+  my_eof(thd);
+  return false;
+}
+
 /**
   This is a wrapper for MYSQL_BIN_LOG::gtid_end_transaction. For normal
   statements, the function gtid_end_transaction is called in the commit
@@ -3046,6 +3114,13 @@ int mysql_execute_command(THD *thd, bool first_level) {
       System_status_var old_status_var = thd->status_var;
       thd->initial_status_var = &old_status_var;
 
+#ifdef HAVE_JEMALLOC
+#ifndef EMBEDDED_LIBRARY
+      extern std::atomic_bool need_update_malloc_status;
+      need_update_malloc_status = true;
+#endif
+#endif
+
       if (!(res = show_precheck(thd, lex, true)))
         res = execute_show(thd, all_tables);
 
@@ -3228,6 +3303,12 @@ int mysql_execute_command(THD *thd, bool first_level) {
       res = ha_show_status(thd, lex->create_info->db_type, HA_ENGINE_TRX);
       break;
     }
+    case SQLCOM_SHOW_MEMORY_STATUS: {
+      if (check_global_access(thd, PROCESS_ACL)) goto error;
+
+      res = show_memory_status(thd);
+      break;
+    }
     case SQLCOM_START_GROUP_REPLICATION: {
       Security_context *sctx = thd->security_context();
       if (!sctx->check_access(SUPER_ACL) &&

sql/sql_yacc.yy

@@ -12631,6 +12631,8 @@ show_param:
             if (prepare_schema_table(YYTHD, lex, 0, SCH_PLUGINS))
               MYSQL_YYABORT;
           }
+        | MEMORY_SYM STATUS_SYM
+          { Lex->sql_command = SQLCOM_SHOW_MEMORY_STATUS; }
         | ENGINE_SYM ident_or_text show_engine_param
           {
             const bool is_temp_table=