| Bug #1987 | myisam_max_sort_file_size is not properly handled | ||
|---|---|---|---|
| Submitted: | 1 Dec 2003 3:30 | Modified: | 1 Dec 2003 8:08 |
| Reporter: | Masaki Fujimoto | Email Updates: | |
| Status: | Not a Bug | Impact on me: | |
| Category: | MySQL Server | Severity: | S3 (Non-critical) |
| Version: | 4.0.16 | OS: | Linux (Debian GNU LInux (Woody)) |
| Assigned to: | CPU Architecture: | Any | |
[1 Dec 2003 7:47]
Dean Ellis
This seems to be handled appropriately (or at least consistently). Per the block_size, values will fall along one megabyte boundaries (rounded down). So, this would not appear to be a bug. Are you, then, making a feature request to be able to specify values that do not have to follow megabyte boundaries? Thank you
[1 Dec 2003 8:03]
Masaki Fujimoto
I think that is not the point, but the problem is that block_size of myisam_max_sort_file_size is set to Mega Bytes in spite of the ChangeLog entry I quoted at the top this report(which says that myisam_max_sort_file_size is now given in bytes). I have no idea that what is the correct behavior, but either current behavior, or the ChangeLog entry should be fixed in any case.
[1 Dec 2003 8:08]
Dean Ellis
The changelog refers only to the way the value is specified: prior to 4.0.3 you specified a number of megabytes; now you specify a number of bytes. The block size itself has not changed.
[1 Dec 2003 8:20]
Masaki Fujimoto
Ah, now I think I've got it. Thank you.
Description: I've found the following ChangeLog Entry at http://www.mysql.com/documentation/mysql/bychapter/manual_News.html#News-4.0.3: * The startup parameters myisam_max_sort_file_size and myisam_max_extra_sort_file_size are now given in bytes, not megabytes. and it seems that myisam_max_sort_file_size is not handled properly (specified values are implicitly changed or ignored). IMHO the option entry in mysqld.cc is the cause of problem (it still handles myisam_max_sort_file_size as Mega Bytes parameter). In line 3947, block_size is still specified as 1024*1024. mysql-4.0.16/sql/mysqld.cc: 3942 {"myisam_max_sort_file_size", OPT_MYISAM_MAX_SORT_FILE_SIZE, 3943 "Don't use the fast sort index method to created index if the temporary file would get bigger than this!", 3944 (gptr*) &global_system_variables.myisam_max_sort_file_size, 3945 (gptr*) &max_system_variables.myisam_max_sort_file_size, 0, 3946 GET_ULL, REQUIRED_ARG, (longlong) LONG_MAX, 0, (ulonglong) MAX_FILE_SIZE, > 3947 0, 1024*1024, 0}, Please see 'How to repeat' for detail. How to repeat: mysql> SET GLOBAL myisam_max_sort_file_size=1; Query OK, 0 rows affected (0.00 sec) mysql> SHOW GLOBAL VARIABLES LIKE 'myisam_max_%'; +---------------------------------+-----------+ | Variable_name | Value | +---------------------------------+-----------+ | myisam_max_extra_sort_file_size | 268435456 | | myisam_max_sort_file_size | 0 | +---------------------------------+-----------+ 2 rows in set (0.00 sec) Suggested fix: $ diff -u mysqld.cc.bak mysqld.cc --- mysqld.cc.bak Mon Dec 1 20:28:12 2003 +++ mysqld.cc Mon Dec 1 20:28:24 2003 @@ -3944,7 +3944,7 @@ (gptr*) &global_system_variables.myisam_max_sort_file_size, (gptr*) &max_system_variables.myisam_max_sort_file_size, 0, GET_ULL, REQUIRED_ARG, (longlong) LONG_MAX, 0, (ulonglong) MAX_FILE_SIZE, - 0, 1024*1024, 0}, + 0, 1, 0}, {"myisam_repair_threads", OPT_MYISAM_REPAIR_THREADS, "Number of threads to use when repairing MyISAM tables. The value of 1 disables parallel repair.", (gptr*) &global_system_variables.myisam_repair_threads,