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1 Reference Manual :: 13.6.3 InnoDB Startup Options and System Variables

innodb_flush_method to O_DIRECT can degrade performance of simple SELECT statements by a factor of three. by uglycharly Nov 16

Linux HugeTLBfs: Improve MySQL Database Application Performance

http://www.cyberciti.biz/tips/linux-hugetlbfs-and-mysql-performance.html A pplications that perform a lot of memory accesses (several GBs) may obtain performance improvements by using large pages due to reduced Translation Lookaside Buffer (TLB) misses.

Michael Tokarev: Re: O_DIRECT question

Linus Torvalds wrote: > > On Thu, 11 Jan 2007, Viktor wrote: >> OK, madvise() used with mmap'ed file allows to have reads from a file >> with zero-copy between kernel/user buffers and don't pollute cache >> memory unnecessarily. But how about writes? https://lkml.org/lkml/2007/1/11/144
http://www.mysqlperformanceblog.com/2007/11/04/heikki-tuuri-answers-to-innodb-questions-part-ii/

Heikki Tuuri answers to Innodb questions, Part II | MySQL Performance Blog

I now got answers to the second portions of the questions you asked Heikki.

il recommande clairement d'utiliser O_DIRECT pour éviter le double buffering by uglycharly Nov 15

Properties: Description: This variable changes the way InnoDB open files and flush data to disk and is should be considered as very important for InnoDB performance. http://optimmysql.blogspot.com/2008/05/variable-day-out-12-innodbflushmethod.html

Variable's Day Out #12: innodb_flush_method

tentative d'explication du risque avec O_DIRECT sans le BBU du contrôleur RAID ou SAN by uglycharly Nov 15

Linux 64-bit, MySQL, Swap and Memory

http://mysqldba.blogspot.com/2008/05/linux-64-bit-mysql-swap-and-memory.html The VM for Linux prefers system cache over application memory.
November 3, 2007 By Peter Zaitsev 39 Comments http://www.mysqlperformanceblog.com/2007/11/03/choosing-innodb_buffer_pool_size/

Choosing innodb_buffer_pool_size | MySQL Performance Blog

très intéressant, innob_db_buffer_size prend en fait deux fois sa taille en ram ! by uglycharly Nov 8

I’m often asked how one can evaluate IO subsystem (Hard drive RAID or SAN) performance for MySQL needs so I’ve decided to write some simple steps you can take to get a good feeling about it, it is not perfect but usually can tell you quite a lot of what you should expect from the system. http://www.mysqlperformanceblog.com/2008/03/05/evaluating-io-subsystem-performance-for-mysql-needs/

Evaluating IO subsystem performance for MySQL Needs | MySQL Performance Blog

Percona MySQL Consulting can often recover lost or corrupted data from MyISAM and InnoDB tables or from corrupted MySQL binary logs and general query logs. We have created special data recovery software that can recover data from InnoDB tables. If you want to try InnoDB data recovery yourself, see Percona Data Recovery Tool for InnoDB . http://www.percona.com/mysql-consulting/data-recovery

Data Recovery - Percona

http://www.randombugs.com/linux/compiling-sysbench-0412-debian.html

Compiling sysbench 0.4.12 for Debian | Random Bugs

Home » Bugs , Debian , Featured , How-to , Linux , Shell

If you want sysbench running on a stable debian release by uglycharly Nov 15

http://kerneltrap.org/node/7563 A thread on the lkml began with a query about using O_DIRECT when opening a file.

Accessing Files With O_DIRECT

In mid 2006, YouTube served approximately 100 million videos in a single day.

IT Conversations | MySQL Conference from O'Reilly Media | Paul Tuckfield

Although most Linux users are familiar with the role of process schedulers, such as the new O(1) scheduler, many users are not so familiar with the role of I/O schedulers.

Kernel Korner - I/O Schedulers

Linux: How to clear the cache from memory Linux has a supposedly good memory management feature that will use up any "extra" RAM you have to cache stuff. This section of the memory being used is SUPPOSED to be freely available to be taken over by any other process that actually needs it, but unfortunately my Linux (three distros now, Mandriva 32 bit, and Mandriva 64 bit, and Opensuse 11 64 bit) thinks that cache memory is too important to move over for anything else that actually needs it.

Linux: How To Clear The Cache From Memory

Dans cet article, je vais tenter d'expliquer les différentes informations que le noyau Linux nous donne au travers du fichier /proc/meminfo . Comme support, je vais afficher les données qui concernent mon système.

La mémoire sous Linux : analyse du fichier /proc/meminfo - Sygus.net

drop_caches | LinuxInsight

Writing to this will cause the kernel to drop clean caches, dentries and inodes from memory, causing that memory to become free. To free pagecache:

The Linux Page Cache and pdflush

énorme cet article mais bien amené ! by uglycharly Nov 9

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