… and Innodb tables on ext3 filesystem. Here is what I found: The fragmentation we speak in this article is filesystem fragmentation or internal table fragmentation… suffers worse than Innodb – Innodb extent allocation works (perhaps would be good option for MyISAM as well) – Innodb suffers fragmentation less if it stores…
Post: Heikki Tuuri Innodb answers - Part I
October 26, 2007 By 19 Comments
…. The first 32 pages of a segment are allocated from ‘fragment extents’ where any individual page can be allocated to whatever… has been done on it by Inaam. Q19: INNODB uses it’s own internal buffer pool but it’s in conflict with the Linux kernel’s buffer pool. In high load situations where INNODB…
Post: Innodb Double Write
August 4, 2006 By 24 Comments
… be internally consistent. It does not matter which page version it is – it could be “current” version in which case Innodb will… just between their execution. Reasons for splitting could be file fragmentation – most file systems use 4K block sizes by default so 16K could use more than one fragment. Also if software RAID is used page may come on…
Post: MySQL Binaries Percona build10
December 11, 2008 By 12 Comments
… | innodb_check_defrag.patch | Session status to check fragmentation of the last InnoDB scan | 1.0 | Percona | GPL | The names are Innodb…) | | innodb_show_hashed_memory.patch | Adds additional information of InnoDB internal hash table memories in SHOW INNODB STATUS | 1.0 | Percona | GPL | | | innodb…
Post: Percona build7 with latest patches
November 14, 2008 By 26 Comments
… | innodb_check_defrag.patch | Session status to check fragmentation of the last InnoDB scan | 1.0 | Percona | GPL | The names are Innodb…) | | innodb_show_hashed_memory.patch | Adds additional information of InnoDB internal hash table memories in SHOW INNODB STATUS | 1.0 | Percona | GPL | | | innodb…
Post: Read Buffers, mmap, malloc and MySQL Performance
September 12, 2007 By 8 Comments
… required size, which can get expensive if virtual memory gets fragmented. A while ago I measured over 10 times slow down over time as memory becomes fragmented with 50.000+ of memory areas mapped. As the gap… for Innodb Buffer Pool and Key Buffer but could be used for other large allocations. Finally this is yet another reasons internal…
Comment: Falcon Storage Engine Design Review
January 12, 2007 By 19 Comments
… it in current Limits section though. Isolation Modes: Innodb, Oracle, PostgreSQL also support MVCC but frequently offer …fit to the old one any more but gets fragmented now right ? Regarding real world applications – very significant …, so there is no insight so far on internal processes which are …
Post: Falcon Storage Engine Design Review
January 12, 2007 By 19 Comments
…, in fact this is what you can get in Innodb (by using its internal hidden primary key) but this functionality is not… may end up in non-recoverable stage. This is why Innodb has “innodb double write buffer”. Jim does not believe this is… I have not found much information about is regarding handling fragmentation – what happens on row updates, are they stored in the…
Post: MySQL Indexing Best Practices: Webinar Questions Followup
August 16, 2012 By 4 Comments
…. For Innodb Table id2 is not needed pas part of second key as PRIMARY key is appended to it internally anyway. For… can slow down your inserts and make primary key significantly fragmented. I also would note there are some MySQL optimizer restrictions… index for “order by desc” indicates a double linked list. Innodb has double linked list – each leaf page contains pointers to…
Comment: InnoDB memory allocation, ulimit, and OpenSUSE
August 31, 2010 By 7 Comments
… possible value that would allow mysqld to start without disabling InnoDB or plain crashing because that is a dangerous game. malloc… the thread stacks. Some for other internal needs of MySQL. Some waste from memory space fragmentation. It would all add up eventually…
