MDEV-12012/MDEV-11969 Can't remove GTIDs for a stale GTID Domain ID

As reported in MDEV-11969 "there's no way to ditch knowledge" about some
domain that is no longer updated on a server. Besides being of annoyance to
clutter output in DBA console stale domains can prevent the slave
to connect the master as MDEV-12012 witnesses.
What domain is obsolete must be evaluated by the user (DBA) according
to whether the domain info is still relevant and will the domain ever
receive any update.

This patch introduces a method to discard obsolete gtid domains from
the server binlog state. The removal requires no event group from such
domain present in existing binlog files though. If there are any the
containing logs must be first PURGEd in order for

  FLUSH BINARY LOGS DELETE_DOMAIN_ID=(list-of-domains)

succeed. Otherwise the command returns an error.

The list of obsolete domains can be computed through
intersecting two sets - the earliest (first) binlog's Gtid_list
and the current value of @@global.gtid_binlog_state - and extracting
the domain id components from the intersection list items.
The new DELETE_DOMAIN_ID featured FLUSH continues to rotate binlog
omitting the deleted domains from the active binlog file's Gtid_list.
Notice though when the command is ineffective - that none of requested to delete
domain exists in the binlog state - rotation does not occur.

Obsolete domain deletion is not harmful for connected slaves as long
as master side binlog files *purge* is synchronized with FLUSH-DELETE_DOMAIN_ID.
The slaves must have the last event from purged files processed as usual,
in order not to bump later into requesting a gtid from a file which
was already gone.
While the command is not replicated (as ordinary FLUSH BINLOG LOGS is)
slaves, even though having extra domains, won't suffer from reconnection errors
thanks to master-slave gtid connection protocol allowing the master
to be ignorant about a gtid domain.
Should at failover such slave to be promoted into master role it may run
the ex-master's

 FLUSH BINARY LOGS DELETE_DOMAIN_ID=(list-of-domains)

to clean its own binlog state.

NOTES.
  suite/perfschema/r/start_server_low_digest.result
is re-recorded as consequence of internal parser codes changes.

12 files changed, 398 insertions, 75 deletions

diff --git a/sql/lex.h b/sql/lex.h
index 85bd20a5f37..6a1cb6653e9 100644
--- a/sql/lex.h
+++ b/sql/lex.h
@@ -179,6 +179,7 @@ static SYMBOL symbols[] = {
   { "DELAYED",		SYM(DELAYED_SYM)},
   { "DELAY_KEY_WRITE",	SYM(DELAY_KEY_WRITE_SYM)},
   { "DELETE",		SYM(DELETE_SYM)},
+  { "DELETE_DOMAIN_ID", SYM(DELETE_DOMAIN_ID_SYM)},
   { "DESC",		SYM(DESC)},
   { "DESCRIBE",		SYM(DESCRIBE)},
   { "DES_KEY_FILE",	SYM(DES_KEY_FILE)},
diff --git a/sql/log.cc b/sql/log.cc
index a9f486d88c1..a0e5e908ca7 100644
--- a/sql/log.cc
+++ b/sql/log.cc
@@ -6622,6 +6622,120 @@ void MYSQL_BIN_LOG::checkpoint_and_purge(ulong binlog_id)
   purge();
 }
 
+
+/**
+  Searches for the first (oldest) binlog file name in in the binlog index.
+
+  @param[in,out]  buf_arg  pointer to a buffer to hold found
+                           the first binary log file name
+  @return         NULL     on success, otherwise error message
+*/
+static const char* get_first_binlog(char* buf_arg)
+{
+  IO_CACHE *index_file;
+  size_t length;
+  char fname[FN_REFLEN];
+  const char* errmsg= NULL;
+
+  DBUG_ENTER("get_first_binlog");
+
+  DBUG_ASSERT(mysql_bin_log.is_open());
+
+  mysql_bin_log.lock_index();
+
+  index_file=mysql_bin_log.get_index_file();
+  if (reinit_io_cache(index_file, READ_CACHE, (my_off_t) 0, 0, 0))
+  {
+    errmsg= "failed to create a cache on binlog index";
+    goto end;
+  }
+  /* The file ends with EOF or empty line */
+  if ((length=my_b_gets(index_file, fname, sizeof(fname))) <= 1)
+  {
+    errmsg= "empty binlog index";
+    goto end;
+  }
+  else
+  {
+    fname[length-1]= 0;                         // Remove end \n
+  }
+  if (normalize_binlog_name(buf_arg, fname, false))
+  {
+    errmsg= "cound not normalize the first file name in the binlog index";
+    goto end;
+  }
+end:
+  mysql_bin_log.unlock_index();
+
+  DBUG_RETURN(errmsg);
+}
+
+/**
+  Check weather the gtid binlog state can safely remove gtid
+  domains passed as the argument. A safety condition is satisfied when
+  there are no events from the being deleted domains in the currently existing
+  binlog files. Upon successful check the supplied domains are removed
+  from @@gtid_binlog_state. The caller is supposed to rotate binlog so that
+  the active latest file won't have the deleted domains in its Gtid_list header.
+
+  @param  domain_drop_lex  gtid domain id sequence from lex.
+                           Passed as a pointer to dynamic array must be not empty
+                           unless pointer value NULL.
+  @retval zero             on success
+  @retval > 0              ineffective call none from the *non* empty
+                           gtid domain sequence is deleted
+  @retval < 0              on error
+*/
+static int do_delete_gtid_domain(DYNAMIC_ARRAY *domain_drop_lex)
+{
+  int rc= 0;
+  Gtid_list_log_event *glev= NULL;
+  char buf[FN_REFLEN];
+  File file;
+  IO_CACHE cache;
+  const char* errmsg= NULL;
+  char errbuf[MYSQL_ERRMSG_SIZE]= {0};
+
+  if (!domain_drop_lex)
+    return 0; // still "effective" having empty domain sequence to delete
+
+  DBUG_ASSERT(domain_drop_lex->elements > 0);
+  mysql_mutex_assert_owner(mysql_bin_log.get_log_lock());
+
+  if ((errmsg= get_first_binlog(buf)) != NULL)
+    goto end;
+  bzero((char*) &cache, sizeof(cache));
+  if ((file= open_binlog(&cache, buf, &errmsg)) == (File) -1)
+    goto end;
+  errmsg= get_gtid_list_event(&cache, &glev);
+  end_io_cache(&cache);
+  mysql_file_close(file, MYF(MY_WME));
+
+  DBUG_EXECUTE_IF("inject_binlog_delete_domain_init_error",
+                  errmsg= "injected error";);
+  if (errmsg)
+    goto end;
+  errmsg= rpl_global_gtid_binlog_state.drop_domain(domain_drop_lex,
+                                                   glev, errbuf);
+
+end:
+  if (errmsg)
+  {
+    if (strlen(errmsg) > 0)
+    {
+      my_error(ER_BINLOG_CANT_DELETE_GTID_DOMAIN, MYF(0), errmsg);
+      rc= -1;
+    }
+    else
+    {
+      rc= 1;
+    }
+  }
+  delete glev;
+
+  return rc;
+}
+
 /**
   The method is a shortcut of @c rotate() and @c purge().
   LOCK_log is acquired prior to rotate and is released after it.
@@ -6631,9 +6745,10 @@ void MYSQL_BIN_LOG::checkpoint_and_purge(ulong binlog_id)
   @retval
     nonzero - error in rotating routine.
 */
-int MYSQL_BIN_LOG::rotate_and_purge(bool force_rotate)
+int MYSQL_BIN_LOG::rotate_and_purge(bool force_rotate,
+                                    DYNAMIC_ARRAY *domain_drop_lex)
 {
-  int error= 0;
+  int err_gtid=0, error= 0;
   ulong prev_binlog_id;
   DBUG_ENTER("MYSQL_BIN_LOG::rotate_and_purge");
   bool check_purge= false;
@@ -6641,7 +6756,14 @@ int MYSQL_BIN_LOG::rotate_and_purge(bool force_rotate)
   //todo: fix the macro def and restore safe_mutex_assert_not_owner(&LOCK_log);
   mysql_mutex_lock(&LOCK_log);
   prev_binlog_id= current_binlog_id;
-  if ((error= rotate(force_rotate, &check_purge)))
+
+  if ((err_gtid= do_delete_gtid_domain(domain_drop_lex)))
+  {
+    // inffective attempt to delete merely skips rotate and purge
+    if (err_gtid < 0)
+      error= 1; // otherwise error is propagated the user
+  }
+  else if ((error= rotate(force_rotate, &check_purge)))
     check_purge= false;
   /*
     NOTE: Run purge_logs wo/ holding LOCK_log because it does not need
@@ -10219,6 +10341,73 @@ TC_LOG_BINLOG::set_status_variables(THD *thd)
   }
 }
 
+
+/*
+  Find the Gtid_list_log_event at the start of a binlog.
+
+  NULL for ok, non-NULL error message for error.
+
+  If ok, then the event is returned in *out_gtid_list. This can be NULL if we
+  get back to binlogs written by old server version without GTID support. If
+  so, it means we have reached the point to start from, as no GTID events can
+  exist in earlier binlogs.
+*/
+const char *
+get_gtid_list_event(IO_CACHE *cache, Gtid_list_log_event **out_gtid_list)
+{
+  Format_description_log_event init_fdle(BINLOG_VERSION);
+  Format_description_log_event *fdle;
+  Log_event *ev;
+  const char *errormsg = NULL;
+
+  *out_gtid_list= NULL;
+
+  if (!(ev= Log_event::read_log_event(cache, 0, &init_fdle,
+                                      opt_master_verify_checksum)) ||
+      ev->get_type_code() != FORMAT_DESCRIPTION_EVENT)
+  {
+    if (ev)
+      delete ev;
+    return "Could not read format description log event while looking for "
+      "GTID position in binlog";
+  }
+
+  fdle= static_cast<Format_description_log_event *>(ev);
+
+  for (;;)
+  {
+    Log_event_type typ;
+
+    ev= Log_event::read_log_event(cache, 0, fdle, opt_master_verify_checksum);
+    if (!ev)
+    {
+      errormsg= "Could not read GTID list event while looking for GTID "
+        "position in binlog";
+      break;
+    }
+    typ= ev->get_type_code();
+    if (typ == GTID_LIST_EVENT)
+      break;                                    /* Done, found it */
+    if (typ == START_ENCRYPTION_EVENT)
+    {
+      if (fdle->start_decryption((Start_encryption_log_event*) ev))
+        errormsg= "Could not set up decryption for binlog.";
+    }
+    delete ev;
+    if (typ == ROTATE_EVENT || typ == STOP_EVENT ||
+        typ == FORMAT_DESCRIPTION_EVENT || typ == START_ENCRYPTION_EVENT)
+      continue;                                 /* Continue looking */
+
+    /* We did not find any Gtid_list_log_event, must be old binlog. */
+    ev= NULL;
+    break;
+  }
+
+  delete fdle;
+  *out_gtid_list= static_cast<Gtid_list_log_event *>(ev);
+  return errormsg;
+}
+
 struct st_mysql_storage_engine binlog_storage_engine=
 { MYSQL_HANDLERTON_INTERFACE_VERSION };
 
diff --git a/sql/log.h b/sql/log.h
index bf076fae31d..3026ca11e31 100644
--- a/sql/log.h
+++ b/sql/log.h
@@ -755,7 +755,7 @@ public:
   int update_log_index(LOG_INFO* linfo, bool need_update_threads);
   int rotate(bool force_rotate, bool* check_purge);
   void checkpoint_and_purge(ulong binlog_id);
-  int rotate_and_purge(bool force_rotate);
+  int rotate_and_purge(bool force_rotate, DYNAMIC_ARRAY* drop_gtid_domain= NULL);
   /**
      Flush binlog cache and synchronize to disk.
 
@@ -1165,4 +1165,9 @@ static inline TC_LOG *get_tc_log_implementation()
   return &tc_log_mmap;
 }
 
+
+class Gtid_list_log_event;
+const char *
+get_gtid_list_event(IO_CACHE *cache, Gtid_list_log_event **out_gtid_list);
+
 #endif /* LOG_H */
diff --git a/sql/rpl_gtid.cc b/sql/rpl_gtid.cc
index 51df8f1a789..7b1acf17ef5 100644
--- a/sql/rpl_gtid.cc
+++ b/sql/rpl_gtid.cc
@@ -26,7 +26,7 @@
 #include "key.h"
 #include "rpl_gtid.h"
 #include "rpl_rli.h"
-
+#include "log_event.h"
 
 const LEX_STRING rpl_gtid_slave_state_table_name=
   { C_STRING_WITH_LEN("gtid_slave_pos") };
@@ -1728,6 +1728,155 @@ end:
   return res;
 }
 
+/**
+  Remove domains supplied by the first argument from binlog state.
+  Removal is done for any domain whose last gtids (from all its servers) match
+  ones in Gtid list event of the 2nd argument.
+
+  @param  ids               gtid domain id sequence, may contain dups
+  @param  glev              pointer to Gtid list event describing
+                            the match condition
+  @param  errbuf [out]      pointer to possible error message array
+
+  @retval NULL              as success when at least one domain is removed
+  @retval ""                empty string to indicate ineffective call
+                            when no domains removed
+  @retval NOT EMPTY string  otherwise an error message
+*/
+const char*
+rpl_binlog_state::drop_domain(DYNAMIC_ARRAY *ids,
+                              Gtid_list_log_event *glev,
+                              char* errbuf)
+{
+  DYNAMIC_ARRAY domain_unique; // sequece (unsorted) of unique element*:s
+  rpl_binlog_state::element* domain_unique_buffer[16];
+  ulong k, l;
+  const char* errmsg= NULL;
+
+  DBUG_ENTER("rpl_binlog_state::drop_domain");
+
+  my_init_dynamic_array2(&domain_unique,
+                         sizeof(element*), domain_unique_buffer,
+                         sizeof(domain_unique_buffer) / sizeof(element*), 4, 0);
+
+  mysql_mutex_lock(&LOCK_binlog_state);
+
+  /*
+    Gtid list is supposed to come from a binlog's Gtid_list event and
+    therefore should be a subset of the current binlog state. That is
+    for every domain in the list the binlog state contains a gtid with
+    sequence number not less than that of the list.
+    Exceptions of this inclusion rule are:
+      A. the list may still refer to gtids from already deleted domains.
+         Files containing them must have been purged whereas the file
+         with the list is not yet.
+      B. out of order groups were injected
+      C. manually build list of binlog files violating the inclusion
+         constraint.
+    While A is a normal case (not necessarily distinguishable from C though),
+    B and C may require the user's attention so any (incl the A's suspected)
+    inconsistency is diagnosed and *warned*.
+  */
+  for (l= 0, errbuf[0]= 0; l < glev->count; l++, errbuf[0]= 0)
+  {
+    rpl_gtid* rb_state_gtid= find_nolock(glev->list[l].domain_id,
+                                         glev->list[l].server_id);
+    if (!rb_state_gtid)
+      sprintf(errbuf,
+              "missing gtids from the '%u-%u' domain-server pair which is "
+              "referred to in the gtid list describing an earlier state. Ignore "
+              "if the domain ('%u') was already explicitly deleted",
+              glev->list[l].domain_id, glev->list[l].server_id,
+              glev->list[l].domain_id);
+    else if (rb_state_gtid->seq_no < glev->list[l].seq_no)
+      sprintf(errbuf,
+              "having a gtid '%u-%u-%llu' which is less than "
+              "the '%u-%u-%llu' of the gtid list describing an earlier state. "
+              "The state may have been affected by manually injecting "
+              "a lower sequence number gtid or via replication",
+              rb_state_gtid->domain_id, rb_state_gtid->server_id,
+              rb_state_gtid->seq_no, glev->list[l].domain_id,
+              glev->list[l].server_id, glev->list[l].seq_no);
+    if (strlen(errbuf)) // use strlen() as cheap flag
+      push_warning_printf(current_thd, Sql_condition::WARN_LEVEL_WARN,
+                          ER_BINLOG_CANT_DELETE_GTID_DOMAIN,
+                          "The current gtid binlog state is incompatible with "
+                          "a former one %s.", errbuf);
+  }
+
+  /*
+    For each domain_id from ids
+      when no such domain in binlog state
+        warn && continue
+      For each domain.server's last gtid
+        when not locate the last gtid in glev.list
+          error out binlog state can't change
+        otherwise continue
+  */
+  for (ulong i= 0; i < ids->elements; i++)
+  {
+    rpl_binlog_state::element *elem= NULL;
+    ulong *ptr_domain_id;
+    bool not_match;
+
+    ptr_domain_id= (ulong*) dynamic_array_ptr(ids, i);
+    elem= (rpl_binlog_state::element *)
+      my_hash_search(&hash, (const uchar *) ptr_domain_id, 0);
+    if (!elem)
+    {
+      push_warning_printf(current_thd, Sql_condition::WARN_LEVEL_WARN,
+                          ER_BINLOG_CANT_DELETE_GTID_DOMAIN,
+                          "The gtid domain being deleted ('%lu') is not in "
+                          "the current binlog state", *ptr_domain_id);
+      continue;
+    }
+
+    for (not_match= true, k= 0; k < elem->hash.records; k++)
+    {
+      rpl_gtid *d_gtid= (rpl_gtid *)my_hash_element(&elem->hash, k);
+      for (ulong l= 0; l < glev->count && not_match; l++)
+        not_match= !(*d_gtid == glev->list[l]);
+    }
+
+    if (not_match)
+    {
+      sprintf(errbuf, "binlog files may contain gtids from the domain ('%lu') "
+              "being deleted. Make sure to first purge those files",
+              *ptr_domain_id);
+      errmsg= errbuf;
+      goto end;
+    }
+    // compose a sequence of unique pointers to domain object
+    for (k= 0; k < domain_unique.elements; k++)
+    {
+      if ((rpl_binlog_state::element*) dynamic_array_ptr(&domain_unique, k)
+          == elem)
+        break; // domain_id's elem has been already in
+    }
+    if (k == domain_unique.elements) // proven not to have duplicates
+      insert_dynamic(&domain_unique, (uchar*) &elem);
+  }
+
+  // Domain removal from binlog state
+  for (k= 0; k < domain_unique.elements; k++)
+  {
+    rpl_binlog_state::element *elem= *(rpl_binlog_state::element**)
+      dynamic_array_ptr(&domain_unique, k);
+    my_hash_free(&elem->hash);
+    my_hash_delete(&hash, (uchar*) elem);
+  }
+
+  DBUG_ASSERT(strlen(errbuf) == 0);
+
+  if (domain_unique.elements == 0)
+    errmsg= "";
+
+end:
+  mysql_mutex_unlock(&LOCK_binlog_state);
+  delete_dynamic(&domain_unique);
+
+  DBUG_RETURN(errmsg);
+}
 
 slave_connection_state::slave_connection_state()
 {
diff --git a/sql/rpl_gtid.h b/sql/rpl_gtid.h
index ece6effbef6..79d566bddbf 100644
--- a/sql/rpl_gtid.h
+++ b/sql/rpl_gtid.h
@@ -34,6 +34,13 @@ struct rpl_gtid
   uint64 seq_no;
 };
 
+inline bool operator==(const rpl_gtid& lhs, const rpl_gtid& rhs)
+{
+  return
+    lhs.domain_id == rhs.domain_id &&
+    lhs.server_id == rhs.server_id &&
+    lhs.seq_no    == rhs.seq_no;
+};
 
 enum enum_gtid_skip_type {
   GTID_SKIP_NOT, GTID_SKIP_STANDALONE, GTID_SKIP_TRANSACTION
@@ -93,6 +100,7 @@ struct gtid_waiting {
 
 class Relay_log_info;
 struct rpl_group_info;
+class Gtid_list_log_event;
 
 /*
   Replication slave state.
@@ -256,6 +264,7 @@ struct rpl_binlog_state
   rpl_gtid *find_nolock(uint32 domain_id, uint32 server_id);
   rpl_gtid *find(uint32 domain_id, uint32 server_id);
   rpl_gtid *find_most_recent(uint32 domain_id);
+  const char* drop_domain(DYNAMIC_ARRAY *ids, Gtid_list_log_event *glev, char*);
 };
 
 
diff --git a/sql/share/errmsg-utf8.txt b/sql/share/errmsg-utf8.txt
index d335b0b420b..15ec98045ea 100644
--- a/sql/share/errmsg-utf8.txt
+++ b/sql/share/errmsg-utf8.txt
@@ -7142,3 +7142,5 @@ ER_NO_EIS_FOR_FIELD
 ER_WARN_AGGFUNC_DEPENDENCE
         eng "Aggregate function '%-.192s)' of SELECT #%d belongs to SELECT #%d"
         ukr "Агрегатна функція '%-.192s)' з SELECTу #%d належить до SELECTу #%d"
+ER_BINLOG_CANT_DELETE_GTID_DOMAIN
+	eng "Could not delete gtid domain. Reason: %s."
diff --git a/sql/sql_lex.cc b/sql/sql_lex.cc
index 8edd9b3fbd8..63ab6b5d046 100644
--- a/sql/sql_lex.cc
+++ b/sql/sql_lex.cc
@@ -800,6 +800,7 @@ void lex_end_stage2(LEX *lex)
 
   /* Reset LEX_MASTER_INFO */
   lex->mi.reset(lex->sql_command == SQLCOM_CHANGE_MASTER);
+  delete_dynamic(&lex->delete_gtid_domain);
 
   DBUG_VOID_RETURN;
 }
@@ -2878,6 +2879,10 @@ LEX::LEX()
                       INITIAL_LEX_PLUGIN_LIST_SIZE, 0);
   reset_query_tables_list(TRUE);
   mi.init();
+  init_dynamic_array2(&delete_gtid_domain, sizeof(ulong*),
+                      gtid_domain_static_buffer,
+                      initial_gtid_domain_buffer_size,
+                      initial_gtid_domain_buffer_size, 0);
 }
 
 
diff --git a/sql/sql_lex.h b/sql/sql_lex.h
index 116ac815ec0..b57fba08b47 100644
--- a/sql/sql_lex.h
+++ b/sql/sql_lex.h
@@ -2726,6 +2726,13 @@ public:
   */
   Item *limit_rows_examined;
   ulonglong limit_rows_examined_cnt;
+  /**
+    Holds a set of domain_ids for deletion at FLUSH..DELETE_DOMAIN_ID
+  */
+  DYNAMIC_ARRAY delete_gtid_domain;
+  static const ulong initial_gtid_domain_buffer_size= 16;
+  ulong gtid_domain_static_buffer[initial_gtid_domain_buffer_size];
+
   inline void set_limit_rows_examined()
   {
     if (limit_rows_examined)
diff --git a/sql/sql_reload.cc b/sql/sql_reload.cc
index d68ce96dc85..73dd9679ed7 100644
--- a/sql/sql_reload.cc
+++ b/sql/sql_reload.cc
@@ -153,7 +153,10 @@ bool reload_acl_and_cache(THD *thd, unsigned long long options,
     tmp_write_to_binlog= 0;
     if (mysql_bin_log.is_open())
     {
-      if (mysql_bin_log.rotate_and_purge(true))
+      DYNAMIC_ARRAY *drop_gtid_domain=
+        (thd && (thd->lex->delete_gtid_domain.elements > 0)) ?
+        &thd->lex->delete_gtid_domain : NULL;
+      if (mysql_bin_log.rotate_and_purge(true, drop_gtid_domain))
         *write_to_binlog= -1;
 
       if (WSREP_ON)
diff --git a/sql/sql_repl.cc b/sql/sql_repl.cc
index 764047e4720..b5cca334891 100644
--- a/sql/sql_repl.cc
+++ b/sql/sql_repl.cc
@@ -30,7 +30,7 @@
 #include <my_dir.h>
 #include "rpl_handler.h"
 #include "debug_sync.h"
-
+#include "log.h"                                // get_gtid_list_event
 
 enum enum_gtid_until_state {
   GTID_UNTIL_NOT_DONE,
@@ -875,72 +875,6 @@ get_binlog_list(MEM_ROOT *memroot)
   DBUG_RETURN(current_list);
 }
 
-/*
-  Find the Gtid_list_log_event at the start of a binlog.
-
-  NULL for ok, non-NULL error message for error.
-
-  If ok, then the event is returned in *out_gtid_list. This can be NULL if we
-  get back to binlogs written by old server version without GTID support. If
-  so, it means we have reached the point to start from, as no GTID events can
-  exist in earlier binlogs.
-*/
-static const char *
-get_gtid_list_event(IO_CACHE *cache, Gtid_list_log_event **out_gtid_list)
-{
-  Format_description_log_event init_fdle(BINLOG_VERSION);
-  Format_description_log_event *fdle;
-  Log_event *ev;
-  const char *errormsg = NULL;
-
-  *out_gtid_list= NULL;
-
-  if (!(ev= Log_event::read_log_event(cache, 0, &init_fdle,
-                                      opt_master_verify_checksum)) ||
-      ev->get_type_code() != FORMAT_DESCRIPTION_EVENT)
-  {
-    if (ev)
-      delete ev;
-    return "Could not read format description log event while looking for "
-      "GTID position in binlog";
-  }
-
-  fdle= static_cast<Format_description_log_event *>(ev);
-
-  for (;;)
-  {
-    Log_event_type typ;
-
-    ev= Log_event::read_log_event(cache, 0, fdle, opt_master_verify_checksum);
-    if (!ev)
-    {
-      errormsg= "Could not read GTID list event while looking for GTID "
-        "position in binlog";
-      break;
-    }
-    typ= ev->get_type_code();
-    if (typ == GTID_LIST_EVENT)
-      break;                                    /* Done, found it */
-    if (typ == START_ENCRYPTION_EVENT)
-    {
-      if (fdle->start_decryption((Start_encryption_log_event*) ev))
-        errormsg= "Could not set up decryption for binlog.";
-    }
-    delete ev;
-    if (typ == ROTATE_EVENT || typ == STOP_EVENT ||
-        typ == FORMAT_DESCRIPTION_EVENT || typ == START_ENCRYPTION_EVENT)
-      continue;                                 /* Continue looking */
-
-    /* We did not find any Gtid_list_log_event, must be old binlog. */
-    ev= NULL;
-    break;
-  }
-
-  delete fdle;
-  *out_gtid_list= static_cast<Gtid_list_log_event *>(ev);
-  return errormsg;
-}
-
 
 /*
   Check if every GTID requested by the slave is contained in this (or a later)
diff --git a/sql/sql_repl.h b/sql/sql_repl.h
index e2000bbca73..37acff3141f 100644
--- a/sql/sql_repl.h
+++ b/sql/sql_repl.h
@@ -82,7 +82,6 @@ int rpl_append_gtid_state(String *dest, bool use_binlog);
 int rpl_load_gtid_state(slave_connection_state *state, bool use_binlog);
 bool rpl_gtid_pos_check(THD *thd, char *str, size_t len);
 bool rpl_gtid_pos_update(THD *thd, char *str, size_t len);
-
 #else
 
 struct LOAD_FILE_IO_CACHE : public IO_CACHE { };
diff --git a/sql/sql_yacc.yy b/sql/sql_yacc.yy
index 3fda8832f6b..f379364e453 100644
--- a/sql/sql_yacc.yy
+++ b/sql/sql_yacc.yy
@@ -1182,6 +1182,7 @@ bool my_yyoverflow(short **a, YYSTYPE **b, ulong *yystacksize);
 %token  DELAYED_SYM
 %token  DELAY_KEY_WRITE_SYM
 %token  DELETE_SYM                    /* SQL-2003-R */
+%token  DELETE_DOMAIN_ID_SYM
 %token  DESC                          /* SQL-2003-N */
 %token  DESCRIBE                      /* SQL-2003-R */
 %token  DES_KEY_FILE
@@ -1951,6 +1952,7 @@ bool my_yyoverflow(short **a, YYSTYPE **b, ulong *yystacksize);
         parse_vcol_expr vcol_opt_specifier vcol_opt_attribute
         vcol_opt_attribute_list vcol_attribute
         explainable_command
+        opt_delete_gtid_domain
 END_OF_INPUT
 
 %type <NONE> call sp_proc_stmts sp_proc_stmts1 sp_proc_stmt
@@ -12762,7 +12764,7 @@ flush_option:
           { Lex->type|= REFRESH_GENERAL_LOG; }
         | SLOW LOGS_SYM
           { Lex->type|= REFRESH_SLOW_LOG; }
-        | BINARY LOGS_SYM
+        | BINARY LOGS_SYM opt_delete_gtid_domain
           { Lex->type|= REFRESH_BINARY_LOG; }
         | RELAY LOGS_SYM optional_connection_name
           {
@@ -12819,6 +12821,24 @@ opt_table_list:
         | table_list {}
         ;
 
+opt_delete_gtid_domain:
+          /* empty */ {}
+        | DELETE_DOMAIN_ID_SYM '=' '(' delete_domain_id_list ')'
+          {}
+        ;
+delete_domain_id_list:
+          /* Empty */
+        | delete_domain_id
+        | delete_domain_id_list ',' delete_domain_id
+        ;
+
+delete_domain_id:
+          ulong_num
+          {
+            insert_dynamic(&Lex->delete_gtid_domain, (uchar*) &($1));
+          }
+        ;
+
 optional_flush_tables_arguments:
           /* empty */        {$$= 0;}
         | AND_SYM DISABLE_SYM CHECKPOINT_SYM {$$= REFRESH_CHECKPOINT; }