manual.texi:

  Make InnoDB startup option samples easier to understand, recommend not setting log files too big, because recovery slow

Docs/manual.texi

@@ -36313,23 +36313,37 @@ the configuration file @file{my.cnf}. @xref{Option files}.
 The only required parameter to use InnoDB is @code{innodb_data_file_path},
 but you should set others if you want to get a better performance.
 
-Suppose you have a Windows NT machine with 128 MB RAM and a single 10 GB
+Suppose you have a Windows NT computer with 128 MB RAM and a single 10 GB
 hard disk.  Below is an example of possible configuration parameters in
 @file{my.cnf} for InnoDB:
 
 @example
-innodb_data_file_path = ibdata1:2000M;ibdata2:2000M
+[mysqld]
+# You can write your other MySQL server options here
+# ...
+#
 innodb_data_home_dir = c:\ibdata
-set-variable = innodb_mirrored_log_groups=1
+#                                            Data files must be able to
+#                                            hold your data and indexes
+innodb_data_file_path = ibdata1:2000M;ibdata2:2000M
+#                                            Set buffer pool size to 50 - 80 %
+#                                            of your computer's memory
+set-variable = innodb_buffer_pool_size=70M
+set-variable = innodb_additional_mem_pool_size=10M
 innodb_log_group_home_dir = c:\iblogs
+#                                            .._log_arch_dir must be the same
+#                                            as .._log_group_home_dir
+innodb_log_arch_dir = c:\iblogs
+innodb_log_archive=0
 set-variable = innodb_log_files_in_group=3
-set-variable = innodb_log_file_size=30M
+#                                            Set the log file size to about
+#                                            15 % of the buffer pool size
+set-variable = innodb_log_file_size=10M
 set-variable = innodb_log_buffer_size=8M
+#                                            Set ..flush_log_at_trx_commit to
+#                                            0 if you can afford losing
+#                                            a few last transactions 
 innodb_flush_log_at_trx_commit=1
-innodb_log_arch_dir = c:\iblogs
-innodb_log_archive=0
-set-variable = innodb_buffer_pool_size=80M
-set-variable = innodb_additional_mem_pool_size=10M
 set-variable = innodb_file_io_threads=4
 set-variable = innodb_lock_wait_timeout=50
 @end example
@@ -36340,27 +36354,44 @@ to be >= 10 MB.
 InnoDB does not create directories:
 you have to create them yourself.
 
-Suppose you have a Linux machine with 512 MB RAM and
+Suppose you have a Linux computer with 512 MB RAM and
 three 20 GB hard disks (at directory paths @file{/},
 @file{/dr2} and @file{/dr3}).
 Below is an example of possible configuration parameters in @file{my.cnf} for
 InnoDB:
 
 @example
-innodb_data_file_path = ibdata/ibdata1:2000M;dr2/ibdata/ibdata2:2000M
+[mysqld]
+# You can write your other MySQL server options here
+# ...
+#
 innodb_data_home_dir = /
-set-variable = innodb_mirrored_log_groups=1
-innodb_log_group_home_dir = /dr3
+#                                            Data files must be able to
+#                                            hold your data and indexes
+innodb_data_file_path = ibdata/ibdata1:2000M;dr2/ibdata/ibdata2:2000M
+#                                            Set buffer pool size to 50 - 80 %
+#                                            of your computer's memory
+set-variable = innodb_buffer_pool_size=350M
+set-variable = innodb_additional_mem_pool_size=20M
+innodb_log_group_home_dir = /dr3/iblogs
+#                                            .._log_arch_dir must be the same
+#                                            as .._log_group_home_dir
+innodb_log_arch_dir = /dr3/iblogs
+innodb_log_archive=0
 set-variable = innodb_log_files_in_group=3
+#                                            Set the log file size to about
+#                                            15 % of the buffer pool size
 set-variable = innodb_log_file_size=50M
 set-variable = innodb_log_buffer_size=8M
+#                                            Set ..flush_log_at_trx_commit to
+#                                            0 if you can afford losing
+#                                            a few last transactions 
 innodb_flush_log_at_trx_commit=1
-innodb_log_arch_dir = /dr3/iblogs
-innodb_log_archive=0
-set-variable = innodb_buffer_pool_size=400M
-set-variable = innodb_additional_mem_pool_size=20M
 set-variable = innodb_file_io_threads=4
 set-variable = innodb_lock_wait_timeout=50
+#innodb_flush_method=fdatasync
+#innodb_fast_shutdown=1
+#set-variable = innodb_thread_concurrency=5
 @end example
 
 Note that we have placed the two data files on different disks.
@@ -36374,6 +36405,10 @@ improve the performance of the database if all data is not placed
 on the same physical disk. Putting log files on a different disk from
 data is very often beneficial for performance.
 
+The combined size of the log files MUST be < 4G in a 32-bit computer,
+and to make recovery reasonably fast you should keep the combined size
+smaller than the buffer pool size.
+
 The meanings of the configuration parameters are the following:
 
 @multitable @columnfractions .30 .70
@@ -36397,7 +36432,9 @@ Number of log files in the log group. InnoDB writes to the files in a
 circular fashion. Value 3 is recommended here.
 @item @code{innodb_log_file_size} @tab 
 Size of each log file in a log group in megabytes. Sensible values range
-from 1M to the size of the buffer pool specified below. The bigger the
+from 1M to 1/nth of the size of the buffer pool specified below, where
+n is the number of log files in the log group.
+The bigger the
 value, the less checkpoint flush activity is needed in the buffer pool,
 saving disk i/o. But bigger log files also mean that recovery will be
 slower in case of a crash. File size restriction as for a data file.
@@ -37100,7 +37137,8 @@ to zero. InnoDB tries to flush the log anyway once in a second,
 though the flush is not guaranteed.
 
 @strong{4.}
-Make your log files big, even as big as the buffer pool. When InnoDB
+Make your log files big, the combined size
+even as big as the buffer pool. When InnoDB
 has written the log files full, it has to write the modified contents
 of the buffer pool to disk in a checkpoint. Small log files will cause many
 unnecessary disk writes. The drawback in big log files is that recovery