Hello Sergei, In going through the archives I found this message which is similar to an issue I am currently having. You mention to "Consult the manual for details." I've check through the on-line manual: http://www.mysql.com/doc/en/index.html specifically, http://www.mysql.com/doc/en/SHOW_VARIABLES.html
Unfortunately, this section does not provide an in-depth explanation of the variables, their settings, suggestions for values, min/max/range, etc. For example, you mention that myisam_max_sort_file_size should be 'big enough for MySQL to use "repair by sort" method'. Can you recommend any guidelines for setting this value? Or pointers to a place in the manual where I can find an explanation or set of guidlines? Currently, I have set myisam_max_sort_file_size to 3,145,728,000 (megabytes? since I'm using 3.23) and myisam_sort_buffer_size to 268,435,456. Yet, my database is still using the "repair with keycache" when I add an index with "alter table ..." BTW, I am using the latest stable version of MySQL (3.23.53a) on a Red Hat Linux 7.1 machine. Thanks in advance for any pointers/suggestions, - Robert ----- Hi! On Nov 05, Quentin Bennett wrote: > Hi, > > When doing an Alter Table, what does state > > Repair with keycache > > Mean, and should it take 27 hours (so far) on a 26,000,000 record table. It means that MySQL - for some reasons - decided to add indexes with old slow method. It can easily take 27 hours for such a big table. Take a look at myisam_max_sort_file_size, myisam_max_extra_sort_file_size varialbles, and myisam_sort_buffer_size. The most important for you is the first one. It should be big enough for MySQL to use "repair by sort" method. Increasing the third can give you additional speed then. Consult the manual for details. Regards, Sergei --------------------------------------------------------------------- Before posting, please check: http://www.mysql.com/manual.php (the manual) http://lists.mysql.com/ (the list archive) To request this thread, e-mail <[EMAIL PROTECTED]> To unsubscribe, e-mail <[EMAIL PROTECTED]> Trouble unsubscribing? Try: http://lists.mysql.com/php/unsubscribe.php
