Bug#26931470: PLEASE BACKPORT TO 5.7: DEFAULT LOG-TC-SIZE TOO SMALL ON POWER - 3 * ( 64K PAGE

This is a backport to 5.7 of

Bug#23014086: DEFAULT LOG-TC-SIZE TOO SMALL ON
              POWER - 3 * ( 64K PAGE SIZE) MINIMIUM NEEDED

The problem was that the memory page size for the memory mapped
transaction coordinator was hardcoded to 8k. This did not work
properly on platforms like ARM64 and PowerPC where the page
size is much larger.

This patch fixes the problem by using my_getpagesize() to get
the page size of the current platform rather than using a hardcoded
value.

This has consequences for and changes the behavior of the
--log-tc-size startup option. The minimum and default value
of the option is now 6 * pagesize. This means it is still
24k on Linux (4k pagesize). The value also now has to be
multiples of pagesize rather than multiples of 8k.

Patch based on contribution from Alexey Kopytov.

(cherry picked from commit e3b09cae22163edfc1951641767b776c8545ad49)

Original backport provided by Daniel Black.

Author: jhauglid

mysql-test/include/mysqld--help.inc

@@ -58,6 +58,8 @@ perl;
     s/\b393216\b/262144/;
     # Replacing port number with string
     s/^port \d+/port ####/;
+    # log-tc-size varies by platform
+    s/^log-tc-size \d+/log-tc-size #####/;
     foreach $var (@env) { s/$ENV{$var}/$var/ }
     next if /use --skip-(use-)?symbolic-links to disable/; # for valgrind, again
     next if $skip;

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

@@ -1362,7 +1362,7 @@ log-syslog-facility daemon
 log-syslog-include-pid TRUE
 log-syslog-tag 
 log-tc tc.log
-log-tc-size 24576
+log-tc-size #####
 log-throttle-queries-not-using-indexes 0
 log-timestamps UTC
 log-warnings 0

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

@@ -1357,7 +1357,7 @@ log-statements-unsafe-for-binlog TRUE
 log-syslog FALSE
 log-syslog-tag 
 log-tc tc.log
-log-tc-size 24576
+log-tc-size #####
 log-throttle-queries-not-using-indexes 0
 log-timestamps UTC
 log-warnings 0

sql/binlog.cc

@@ -9511,15 +9511,16 @@ int MYSQL_BIN_LOG::recover(IO_CACHE *log, Format_description_log_event *fdle,
     is partially written to the binlog.
   */
   bool in_transaction= FALSE;
+  int memory_page_size= my_getpagesize();
 
   if (! fdle->is_valid() ||
-      my_hash_init(&xids, &my_charset_bin, TC_LOG_PAGE_SIZE/3, 0,
-                   sizeof(my_xid), 0, 0, MYF(0),
+      my_hash_init(&xids, &my_charset_bin, memory_page_size/3, 0,
+                   sizeof(my_xid), 0, 0, 0,
                    key_memory_binlog_recover_exec))
     goto err1;
 
   init_alloc_root(key_memory_binlog_recover_exec,
-                  &mem_root, TC_LOG_PAGE_SIZE, TC_LOG_PAGE_SIZE);
+                  &mem_root, memory_page_size, memory_page_size);
 
   while ((ev= Log_event::read_log_event(log, 0, fdle, TRUE))
          && ev->is_valid())

sql/mysqld.cc

@@ -314,6 +314,8 @@ bool opt_endinfo, using_udf_functions;
 my_bool locked_in_memory;
 bool opt_using_transactions;
 bool volatile abort_loop;
+ulong opt_tc_log_size;
+
 static enum_server_operational_state server_operational_state= SERVER_BOOTING;
 ulong log_warnings;
 bool  opt_log_syslog_enable;
@@ -5736,8 +5738,9 @@ struct my_option my_long_options[]=
    REQUIRED_ARG, 0, 0, 0, 0, 0, 0},
   {"log-tc-size", 0, "Size of transaction coordinator log.",
    &opt_tc_log_size, &opt_tc_log_size, 0, GET_ULONG,
-   REQUIRED_ARG, TC_LOG_MIN_SIZE, TC_LOG_MIN_SIZE, ULONG_MAX, 0,
-   TC_LOG_PAGE_SIZE, 0},
+   REQUIRED_ARG, TC_LOG_MIN_PAGES * my_getpagesize(),
+   TC_LOG_MIN_PAGES * my_getpagesize(), ULONG_MAX, 0,
+   my_getpagesize(), 0},
   {"master-info-file", 0,
    "The location and name of the file that remembers the master and where "
    "the I/O replication thread is in the master's binlogs.",

sql/tc_log.cc

@@ -85,7 +85,6 @@ ulong tc_log_page_waits= 0;
 
 static const char tc_log_magic[]={(char) 254, 0x23, 0x05, 0x74};
 
-ulong opt_tc_log_size= TC_LOG_MIN_SIZE;
 ulong tc_log_max_pages_used=0, tc_log_page_size=0, tc_log_cur_pages_used=0;
 
 int TC_LOG_MMAP::open(const char *opt_name)
@@ -98,10 +97,6 @@ int TC_LOG_MMAP::open(const char *opt_name)
   DBUG_ASSERT(opt_name && opt_name[0]);
 
   tc_log_page_size= my_getpagesize();
-  if (TC_LOG_PAGE_SIZE > tc_log_page_size)
-  {
-    DBUG_ASSERT(TC_LOG_PAGE_SIZE % tc_log_page_size == 0);
-  }
 
   fn_format(logname,opt_name,mysql_data_home,"",MY_UNPACK_FILENAME);
   if ((fd= mysql_file_open(key_file_tclog, logname, O_RDWR, MYF(0))) < 0)

sql/tc_log.h

@@ -1,4 +1,4 @@
-/* Copyright (c) 2015, Oracle and/or its affiliates. All rights reserved.
+/* Copyright (c) 2015, 2017, Oracle and/or its affiliates. All rights reserved.
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -23,6 +23,7 @@
 class THD;
 typedef ulonglong my_xid;
 
+#define TC_LOG_MIN_PAGES   6
 
 /**
   Transaction Coordinator Log.