Re: Optimizing InnoDB tables
Hi Andre, Thanks for your reply. I have checked the link and my configuration. Innodb_file_per_table is enabled and in data directory appears a set of files by each table. Any ideas? Thanks in advance. Regards, Antonio.
Re: Optimizing InnoDB tables
Am 27.06.2014 09:48, schrieb Antonio Fernández Pérez: Thanks for your reply. I have checked the link and my configuration. Innodb_file_per_table is enabled and in data directory appears a set of files by each table. Any ideas? ideas for what? * which files don't get shrinked (ls -lha) * which evidence do you have that they should * show create table * what *exactly* do you enter in your myscl client signature.asc Description: OpenPGP digital signature
Re: Optimizing InnoDB tables
Hi Reindl, Thanks for your attention. Following the previous mail, I have checked my MySQL's configuration and innodb_file_per_table is enabled so, I think that this parameter not affects directly to fragmented tables in InnoDB (In this case). I would like to know, if is possible, why after execute an analyze table command on some fragmented table, after that, appears fragmented again. Regards, Antonio.
Re: Optimizing InnoDB tables
Hello Antonio, On 6/27/2014 9:31 AM, Antonio Fernández Pérez wrote: Hi Reindl, Thanks for your attention. Following the previous mail, I have checked my MySQL's configuration and innodb_file_per_table is enabled so, I think that this parameter not affects directly to fragmented tables in InnoDB (In this case). I would like to know, if is possible, why after execute an analyze table command on some fragmented table, after that, appears fragmented again. Regards, Antonio. InnoDB operates by storing multiple rows on pages. Each page is 16K. Of that 1K is reserved for metadata (a tiny index showing where on a page each row sits, links to various other locations, checksums, ...) The remaining 15K can be used for your actual data. If you delete a row of data, that space on a page is made available but the page does not change size. It is always 16K. InnoDB stores data in the order of your PK. If you need to insert a new row between other rows on a 'full' page, then the page needs to split. This creates 2 new pages that are about 50% full. If two adjacent pages (A and B) become too 'empty' they can be combined into one page. This puts the data from both pages onto one of them (page A, for example). However page B remains empty and becomes available for any other purpose. Is that what you are calling 'fragmentation' ? -- Shawn Green MySQL Senior Principal Technical Support Engineer Oracle USA, Inc. - Hardware and Software, Engineered to Work Together. Office: Blountville, TN -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe:http://lists.mysql.com/mysql
Re: Optimizing InnoDB tables
- Original Message - From: Antonio Fernández Pérez antoniofernan...@fabergames.com Subject: Re: Optimizing InnoDB tables I would like to know, if is possible, why after execute an analyze table command on some fragmented table, after that, appears fragmented again. Simple question: why do you believe this is a problem? -- Unhappiness is discouraged and will be corrected with kitten pictures. -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe:http://lists.mysql.com/mysql
