Merge heikki@bk-internal.mysql.com:/home/bk/mysql-5.0

into hundin.mysql.fi:/home/heikki/mysql-5.0

sql/ha_innodb.cc

@@ -45,10 +45,58 @@ have disables the InnoDB inlining in this file. */
 
 #include "ha_innodb.h"
 
-pthread_mutex_t innobase_share_mutex, // to protect innobase_open_files
-                prepare_commit_mutex; // to force correct commit order in binlog
+pthread_mutex_t innobase_share_mutex, /* to protect innobase_open_files */
+                prepare_commit_mutex; /* to force correct commit order in
+				      binlog */
 bool innodb_inited= 0;
 
+/*-----------------------------------------------------------------*/
+/* These variables are used to implement (semi-)synchronous MySQL binlog
+replication for InnoDB tables. */
+
+pthread_cond_t  innobase_repl_cond;             /* Posix cond variable;
+                                                this variable is signaled
+                                                when enough binlog has been
+                                                sent to slave, so that a
+                                                waiting trx can return the
+                                                'ok' message to the client
+                                                for a commit */
+pthread_mutex_t innobase_repl_cond_mutex;       /* Posix cond variable mutex
+                                                that also protects the next
+                                                innobase_repl_... variables */
+uint            innobase_repl_state;            /* 1 if synchronous replication
+                                                is switched on and is working
+                                                ok; else 0 */
+uint            innobase_repl_file_name_inited  = 0; /* This is set to 1 when
+                                                innobase_repl_file_name
+                                                contains meaningful data */
+char*           innobase_repl_file_name;        /* The binlog name up to which
+                                                we have sent some binlog to
+                                                the slave */
+my_off_t        innobase_repl_pos;              /* The position in that file
+                                                up to which we have sent the
+                                                binlog to the slave */
+uint            innobase_repl_n_wait_threads    = 0; /* This tells how many
+                                                transactions currently are
+                                                waiting for the binlog to be
+                                                sent to the client */
+uint            innobase_repl_wait_file_name_inited = 0; /* This is set to 1
+                                                when we know the 'smallest'
+                                                wait position */
+char*           innobase_repl_wait_file_name;   /* NULL, or the 'smallest'
+                                                innobase_repl_file_name that
+                                                a transaction is waiting for */
+my_off_t        innobase_repl_wait_pos;         /* The smallest position in
+                                                that file that a trx is
+                                                waiting for: the trx can
+                                                proceed and send an 'ok' to
+                                                the client when MySQL has sent
+                                                the binlog up to this position
+                                                to the slave */
+/*-----------------------------------------------------------------*/
+
+
+
 /* Store MySQL definition of 'byte': in Linux it is char while InnoDB
 uses unsigned char; the header univ.i which we include next defines
 'byte' as a macro which expands to 'unsigned char' */
@@ -1531,10 +1579,10 @@ innobase_commit(
 	DBUG_RETURN(0);
 }
 
-/* The following defined-out code will be enabled later when we put the
+/* TODO: put the
 MySQL-4.1 functionality back to 5.0. This is needed to get InnoDB Hot Backup
 to work. */
-#if 0
+
 /*********************************************************************
 This is called when MySQL writes the binlog entry for the current
 transaction. Writes to the InnoDB tablespace info which tells where the
@@ -1563,6 +1611,24 @@ innobase_report_binlog_offset_and_commit(
 	trx->mysql_log_file_name = log_file_name;
 	trx->mysql_log_offset = (ib_longlong)end_offset;
 
+        if (thd->variables.sync_replication) {
+                /* Let us store the binlog file name and the position, so that
+                we know how long to wait for the binlog to the replicated to
+                the slave in synchronous replication. */
+
+                if (trx->repl_wait_binlog_name == NULL) {
+
+                        trx->repl_wait_binlog_name =
+                                        (char*)mem_alloc(FN_REFLEN + 100);
+                }
+
+                ut_a(strlen(log_file_name) <= FN_REFLEN + 100);
+
+                strcpy(trx->repl_wait_binlog_name, log_file_name);
+
+                trx->repl_wait_binlog_pos = (ib_longlong)end_offset;
+        }
+
 	trx->flush_log_later = TRUE;
 
 	innobase_commit(thd, trx_handle);
@@ -1572,6 +1638,7 @@ innobase_report_binlog_offset_and_commit(
 	return(0);
 }
 
+#if 0
 /***********************************************************************
 This function stores the binlog offset and flushes logs. */
 
@@ -1602,7 +1669,6 @@ innobase_store_binlog_offset_and_flush_log(
 	/* Syncronous flush of the log buffer to disk */
 	log_buffer_flush_to_disk();
 }
-
 #endif
 
 /*********************************************************************
@@ -1615,7 +1681,10 @@ innobase_commit_complete(
                                 /* out: 0 */
         THD*    thd)            /* in: user thread */
 {
+	struct timespec abstime;
 	trx_t*	trx;
+	int	cmp;
+	int	ret;
 
         trx = (trx_t*) thd->ha_data[innobase_hton.slot];
 
@@ -1631,9 +1700,215 @@ innobase_commit_complete(
                 trx_commit_complete_for_mysql(trx);
         }
 
+        printf("Wait binlog name %s, repl state %lu\n",
+                        trx->repl_wait_binlog_name,
+                        (uint)innobase_repl_state);
+
+        if (thd->variables.sync_replication
+            && trx->repl_wait_binlog_name
+            && innobase_repl_state != 0) {
+
+                /* In synchronous replication, let us wait until the MySQL
+                replication has sent the relevant binlog segment to the
+                replication slave. */
+
+/* TODO: Make sure MySQL uses some way (TCP_NODELAY?) to ensure that the data
+has been received in the slave! */
+
+                pthread_mutex_lock(&innobase_repl_cond_mutex);
+try_again:
+                if (innobase_repl_state == 0) {
+
+                        pthread_mutex_unlock(&innobase_repl_cond_mutex);
+
+                        return(0);
+                }
+
+                cmp = strcmp(innobase_repl_file_name,
+                                        trx->repl_wait_binlog_name);
+                if (cmp > 0
+                    || (cmp == 0 && innobase_repl_pos
+                                    >= (my_off_t)trx->repl_wait_binlog_pos)) {
+                        /* We have already sent the relevant binlog to the
+                        slave: no need to wait here */
+
+                        pthread_mutex_unlock(&innobase_repl_cond_mutex);
+
+/*                      printf("Binlog now sent\n"); */
+
+                        return(0);
+                }
+
+                /* Let us update the info about the minimum binlog position
+                of waiting threads in the innobase_repl_... variables */
+
+                if (innobase_repl_wait_file_name_inited != 0) {
+                        cmp = strcmp(trx->repl_wait_binlog_name,
+                                        innobase_repl_wait_file_name);
+                        if (cmp < 0
+                            || (cmp == 0 && (my_off_t)trx->repl_wait_binlog_pos
+                                         <= innobase_repl_wait_pos)) {
+                                /* This thd has an even lower position, let
+                                us update the minimum info */
+
+                                strcpy(innobase_repl_wait_file_name,
+                                        trx->repl_wait_binlog_name);
+
+                                innobase_repl_wait_pos =
+                                        trx->repl_wait_binlog_pos;
+                        }
+                } else {
+                        strcpy(innobase_repl_wait_file_name,
+                                                trx->repl_wait_binlog_name);
+
+                        innobase_repl_wait_pos = trx->repl_wait_binlog_pos;
+
+                        innobase_repl_wait_file_name_inited = 1;
+                }
+                set_timespec(abstime, thd->variables.sync_replication_timeout);
+
+                /* Let us suspend this thread to wait on the condition;
+                when replication has progressed far enough, we will release
+                these waiting threads. The following call
+                pthread_cond_timedwait also atomically unlocks
+                innobase_repl_cond_mutex. */
+
+                innobase_repl_n_wait_threads++;
+
+/*              printf("Waiting for binlog to be sent\n"); */
+
+                ret = pthread_cond_timedwait(&innobase_repl_cond,
+                                        &innobase_repl_cond_mutex, &abstime);
+                innobase_repl_n_wait_threads--;
+
+                if (ret != 0) {
+                        ut_print_timestamp(stderr);
+
+                        fprintf(stderr,
+"  InnoDB: Error: MySQL synchronous replication\n"
+"InnoDB: was not able to send the binlog to the slave within the\n"
+"InnoDB: timeout %lu. We assume that the slave has become inaccessible,\n"
+"InnoDB: and switch off synchronous replication until the communication.\n"
+"InnoDB: to the slave works again.\n",
+				thd->variables.sync_replication_timeout);
+                        fprintf(stderr,
+"InnoDB: MySQL synchronous replication has sent binlog\n"
+"InnoDB: to the slave up to file %s, position %lu\n", innobase_repl_file_name,
+                                        (ulong)innobase_repl_pos);
+                        fprintf(stderr,
+"InnoDB: This transaction needs it to be sent up to\n"
+"InnoDB: file %s, position %lu\n", trx->repl_wait_binlog_name,
+                                        (uint)trx->repl_wait_binlog_pos);
+
+                        innobase_repl_state = 0;
+
+                        pthread_mutex_unlock(&innobase_repl_cond_mutex);
+
+                        return(0);
+                }
+
+                goto try_again;
+        }
+
 	return(0);
 }
 
+/*********************************************************************
+In synchronous replication, reports to InnoDB up to which binlog position
+we have sent the binlog to the slave. Note that replication is synchronous
+for one slave only. For other slaves, we do nothing in this function. This
+function is used in a replication master. */
+
+int
+innobase_repl_report_sent_binlog(
+/*=============================*/
+                                /* out: 0 */
+        THD*    thd,            /* in: thread doing the binlog communication to
+                                the slave */
+        char*   log_file_name,  /* in: binlog file name */
+        my_off_t end_offset)    /* in: the offset in the binlog file up to
+                                which we sent the contents to the slave */
+{
+        int     cmp;
+        ibool   can_release_threads     = 0;
+
+        /* If synchronous replication is not switched on, or this thd is
+        sending binlog to a slave where we do not need synchronous replication,
+        then return immediately */
+
+        if (thd->server_id != thd->variables.sync_replication_slave_id) {
+
+                /* Do nothing */
+
+                return(0);
+        }
+
+        pthread_mutex_lock(&innobase_repl_cond_mutex);
+
+        if (innobase_repl_state == 0) {
+
+                ut_print_timestamp(stderr);
+                fprintf(stderr,
+"  InnoDB: Switching MySQL synchronous replication on again at\n"
+"InnoDB: binlog file %s, position %lu\n", log_file_name, (ulong)end_offset);
+
+                innobase_repl_state = 1;
+        }
+
+        /* The position should increase monotonically, since just one thread
+        is sending the binlog to the slave for which we want synchronous
+        replication. Let us check this, and print an error to the .err log
+        if that is not the case. */
+
+        if (innobase_repl_file_name_inited) {
+                cmp = strcmp(log_file_name, innobase_repl_file_name);
+
+                if (cmp < 0
+                    || (cmp == 0 && end_offset < innobase_repl_pos)) {
+
+                        ut_print_timestamp(stderr);
+                        fprintf(stderr,
+"  InnoDB: Error: MySQL synchronous replication has sent binlog\n"
+"InnoDB: to the slave up to file %s, position %lu\n", innobase_repl_file_name,
+                                        (ulong)innobase_repl_pos);
+                        fprintf(stderr,
+"InnoDB: but now MySQL reports that it sent the binlog only up to\n"
+"InnoDB: file %s, position %lu\n", log_file_name, (ulong)end_offset);
+
+                }
+        }
+
+        strcpy(innobase_repl_file_name, log_file_name);
+        innobase_repl_pos = end_offset;
+        innobase_repl_file_name_inited = 1;
+
+        if (innobase_repl_n_wait_threads > 0) {
+                /* Let us check if some of the waiting threads doing a trx
+                commit can now proceed */
+
+                cmp = strcmp(innobase_repl_file_name,
+                                        innobase_repl_wait_file_name);
+                if (cmp > 0
+                    || (cmp == 0 && innobase_repl_pos
+                                    >= innobase_repl_wait_pos)) {
+
+                        /* Yes, at least one waiting thread can now proceed:
+                        let us release all waiting threads with a broadcast */
+
+                        can_release_threads = 1;
+
+                        innobase_repl_wait_file_name_inited = 0;
+                }
+        }
+
+        pthread_mutex_unlock(&innobase_repl_cond_mutex);
+
+        if (can_release_threads) {
+
+                pthread_cond_broadcast(&innobase_repl_cond);
+        }
+}
+
 /*********************************************************************
 Rolls back a transaction or the latest SQL statement. */
 

sql/ha_innodb.h

@@ -321,3 +321,5 @@ int innobase_rollback_by_xid(
 int innobase_xa_end(THD *thd);
 
 
+int innobase_repl_report_sent_binlog(THD *thd, char *log_file_name,
+                               my_off_t end_offset);

sql/handler.cc

@@ -2411,3 +2411,60 @@ TYPELIB *ha_known_exts(void)
   }
   return &known_extensions;
 }
+
+/*
+  Reports to table handlers up to which position we have sent the binlog
+  to a slave in replication
+
+  SYNOPSIS
+    ha_repl_report_sent_binlog()
+
+  NOTES
+    Only works for InnoDB at the moment
+
+  RETURN VALUE
+    Always 0 (= success)  
+
+  PARAMETERS
+    THD    *thd             in: thread doing the binlog communication to
+                                the slave
+    char   *log_file_name   in: binlog file name
+    my_off_t end_offset     in: the offset in the binlog file up to
+                                which we sent the contents to the slave
+*/
+
+int ha_repl_report_sent_binlog(THD *thd, char *log_file_name,
+                               my_off_t end_offset)
+{
+#ifdef HAVE_INNOBASE_DB
+  return innobase_repl_report_sent_binlog(thd,log_file_name,end_offset);
+#else
+  /* remove warnings about unused parameters */
+  thd=thd; log_file_name=log_file_name; end_offset=end_offset;
+  return 0;
+#endif
+}
+
+/*
+  Reports to table handlers that we stop replication to a specific slave
+
+  SYNOPSIS
+    ha_repl_report_replication_stop()
+
+  NOTES
+    Does nothing at the moment
+
+  RETURN VALUE
+    Always 0 (= success)  
+
+  PARAMETERS
+    THD    *thd             in: thread doing the binlog communication to
+                                the slave
+*/
+
+int ha_repl_report_replication_stop(THD *thd)
+{
+  thd = thd;
+
+  return 0;
+}

sql/handler.h

@@ -843,7 +843,7 @@ int ha_change_key_cache_param(KEY_CACHE *key_cache);
 int ha_change_key_cache(KEY_CACHE *old_key_cache, KEY_CACHE *new_key_cache);
 int ha_end_key_cache(KEY_CACHE *key_cache);
 
-/* weird stuff */
+/* report to InnoDB that control passes to the client */
 int ha_release_temporary_latches(THD *thd);
 
 /* transactions: interface to handlerton functions */
@@ -875,3 +875,7 @@ void trans_register_ha(THD *thd, bool all, handlerton *ht);
 #define trans_need_2pc(thd, all)                   ((total_ha_2pc > 1) && \
         !((all ? &thd->transaction.all : &thd->transaction.stmt)->no_2pc))
 
+/* semi-synchronous replication */
+int ha_repl_report_sent_binlog(THD *thd, char *log_file_name,
+                               my_off_t end_offset);
+int ha_repl_report_replication_stop(THD *thd);

sql/mysqld.cc

@@ -5495,7 +5495,6 @@ The minimum value for this variable is 4096.",
   {"sync-frm", OPT_SYNC_FRM, "Sync .frm to disk on create. Enabled by default.",
    (gptr*) &opt_sync_frm, (gptr*) &opt_sync_frm, 0, GET_BOOL, NO_ARG, 1, 0,
    0, 0, 0, 0},
-#ifdef DOES_NOTHING_YET
   {"sync-replication", OPT_SYNC_REPLICATION,
    "Enable synchronous replication.",
    (gptr*) &global_system_variables.sync_replication,
@@ -5511,7 +5510,6 @@ The minimum value for this variable is 4096.",
    (gptr*) &global_system_variables.sync_replication_timeout,
    (gptr*) &global_system_variables.sync_replication_timeout,
    0, GET_ULONG, REQUIRED_ARG, 10, 0, ~0L, 0, 1, 0},
-#endif
   {"table_cache", OPT_TABLE_CACHE,
    "The number of open tables for all threads.", (gptr*) &table_cache_size,
    (gptr*) &table_cache_size, 0, GET_ULONG, REQUIRED_ARG, 64, 1, 512*1024L,

sql/set_var.cc

@@ -956,11 +956,9 @@ struct show_var_st init_vars[]= {
   {"sql_warnings",            (char*) &sys_sql_warnings,            SHOW_BOOL},
 #ifdef HAVE_REPLICATION
   {sys_sync_binlog_period.name,(char*) &sys_sync_binlog_period,     SHOW_SYS},
-#ifdef DOES_NOTHING_YET
   {sys_sync_replication.name, (char*) &sys_sync_replication,        SHOW_SYS},
   {sys_sync_replication_slave_id.name, (char*) &sys_sync_replication_slave_id,SHOW_SYS},
   {sys_sync_replication_timeout.name, (char*) &sys_sync_replication_timeout,SHOW_SYS},
-#endif
 #endif
   {sys_sync_frm.name,         (char*) &sys_sync_frm,               SHOW_SYS},
 #ifdef HAVE_TZNAME

sql/sql_repl.cc

@@ -385,6 +385,11 @@ impossible position";
     goto err;
   }
 
+  printf("Binlog file name %s\n", log_file_name);
+
+  if (thd->variables.sync_replication)
+    ha_repl_report_sent_binlog(thd, log_file_name, pos);
+
   /*
     We need to start a packet with something other than 255
     to distinguish it from error
@@ -470,6 +475,10 @@ impossible position";
            my_errno= ER_UNKNOWN_ERROR;
            goto err;
          }
+
+         if (thd->variables.sync_replication)
+           ha_repl_report_sent_binlog(thd, log_file_name, my_b_tell(&log));
+
          /*
            No need to save this event. We are only doing simple reads
            (no real parsing of the events) so we don't need it. And so
@@ -527,6 +536,13 @@ impossible position";
 	my_errno= ER_UNKNOWN_ERROR;
 	goto err;
       }
+
+      printf("Dump loop: %s: Current log position %lu\n", log_file_name,
+                  (ulong)my_b_tell(&log));
+
+      if (thd->variables.sync_replication)
+        ha_repl_report_sent_binlog(thd, log_file_name, my_b_tell(&log));
+
       DBUG_PRINT("info", ("log event code %d",
 			  (*packet)[LOG_EVENT_OFFSET+1] ));
       if ((*packet)[LOG_EVENT_OFFSET+1] == LOAD_EVENT)
@@ -640,6 +656,12 @@ impossible position";
 	    goto err;
 	  }
 
+          printf("Second loop: %s: Current log position %lu\n", log_file_name,
+                  (ulong)my_b_tell(&log));
+
+          if (thd->variables.sync_replication)
+            ha_repl_report_sent_binlog(thd, log_file_name, my_b_tell(&log));
+
 	  if ((*packet)[LOG_EVENT_OFFSET+1] == LOAD_EVENT)
 	  {
 	    if (send_file(thd))
@@ -704,12 +726,22 @@ impossible position";
 	my_errno= ER_MASTER_FATAL_ERROR_READING_BINLOG;
 	goto err;
       }
+
+      if (thd->variables.sync_replication)
+        ha_repl_report_sent_binlog(thd, log_file_name, 0);
+
+      printf("Binlog file name of a new binlog %s\n", log_file_name);
+
       packet->length(0);
       packet->append('\0');
     }
   }
 
 end:
+  printf("Ending replication\n");
+  if (thd->variables.sync_replication)
+    ha_repl_report_replication_stop(thd);
+
   end_io_cache(&log);
   (void)my_close(file, MYF(MY_WME));
 
@@ -721,6 +753,11 @@ end:
   DBUG_VOID_RETURN;
 
 err:
+  if (thd->variables.sync_replication)
+    ha_repl_report_replication_stop(thd);
+
+  printf("Ending replication in error %s\n", errmsg);
+
   thd->proc_info = "Waiting to finalize termination";
   end_io_cache(&log);
   /*