Comments on: Estimating user data vs. spinning disk http://www.dbms2.com/2008/09/01/estimating-user-data-vs-spinning-disk/ Choices in data management and analysis Thu, 09 Feb 2012 13:48:12 +0000 hourly 1 http://wordpress.org/?v=3.0.3 By: Infology.Ru » Blog Archive » Оценивая КПД системы хранения: какую долю объема системы хранения занимают данные пользователя http://www.dbms2.com/2008/09/01/estimating-user-data-vs-spinning-disk/#comment-100116 Infology.Ru » Blog Archive » Оценивая КПД системы хранения: какую долю объема системы хранения занимают данные пользователя Tue, 21 Oct 2008 21:14:21 +0000 http://www.dbms2.com/?p=513#comment-100116 [...] Автор: Curt Monash Дата публикации оригинала: 2008-09-01 Перевод: Олег Кузьменко Источник: Блог Курта Монаша [...] [...] Автор: Curt Monash Дата публикации оригинала: 2008-09-01 Перевод: Олег Кузьменко Источник: Блог Курта Монаша [...]

]]> By: Oracle Exadata list pricing | DBMS2 -- DataBase Management System Services http://www.dbms2.com/2008/09/01/estimating-user-data-vs-spinning-disk/#comment-98073 Oracle Exadata list pricing | DBMS2 -- DataBase Management System Services Sun, 28 Sep 2008 05:46:45 +0000 http://www.dbms2.com/?p=513#comment-98073 [...] x 300 MB and 12 x 1 TB of spinning disk respectively. That’s a 1:3.6 ratio, vs. the 1:8 ratio Greenplum quotes. Differences include 4% of Greenplum’s disks being used for hot spares (Oracle’s [...] [...] x 300 MB and 12 x 1 TB of spinning disk respectively. That’s a 1:3.6 ratio, vs. the 1:8 ratio Greenplum quotes. Differences include 4% of Greenplum’s disks being used for hot spares (Oracle’s [...]

]]> By: Head to head blog debate between EMC, NetApp, and HP | DBMS2 -- DataBase Management System Services http://www.dbms2.com/2008/09/01/estimating-user-data-vs-spinning-disk/#comment-96663 Head to head blog debate between EMC, NetApp, and HP | DBMS2 -- DataBase Management System Services Thu, 04 Sep 2008 02:00:36 +0000 http://www.dbms2.com/?p=513#comment-96663 [...] recent foray into measuring disk storage pales by comparison. Share: These icons link to social bookmarking sites where readers can share [...] [...] recent foray into measuring disk storage pales by comparison. Share: These icons link to social bookmarking sites where readers can share [...]

]]> By: Introduction to Aster Data and nCluster | DBMS2 -- DataBase Management System Services http://www.dbms2.com/2008/09/01/estimating-user-data-vs-spinning-disk/#comment-96518 Introduction to Aster Data and nCluster | DBMS2 -- DataBase Management System Services Tue, 02 Sep 2008 08:56:16 +0000 http://www.dbms2.com/?p=513#comment-96518 [...] has 360 terabytes of spinning disk, which suggests the implementation there might have one level less of redundancy than some other systems [...] [...] has 360 terabytes of spinning disk, which suggests the implementation there might have one level less of redundancy than some other systems [...]

]]> By: Luke Lonergan http://www.dbms2.com/2008/09/01/estimating-user-data-vs-spinning-disk/#comment-96507 Luke Lonergan Tue, 02 Sep 2008 06:52:32 +0000 http://www.dbms2.com/?p=513#comment-96507 Yep - it's right enough, but confusing! One key thing to note - only the RAID10 consumes spindles, the rest of the overhead consumes space on the devices. Spindles are expensive, space is dirt cheap. In other words, with RAID10, you need physically distinct devices to enable fault tolerance. The inter-host mirroring we provide consumes disk *space* on mirror hosts, allocated from the same group of RAID'ed spindles that the primary space is on. Yep – it’s right enough, but confusing!

One key thing to note – only the RAID10 consumes spindles, the rest of the overhead consumes space on the devices. Spindles are expensive, space is dirt cheap.

In other words, with RAID10, you need physically distinct devices to enable fault tolerance.

The inter-host mirroring we provide consumes disk *space* on mirror hosts, allocated from the same group of RAID’ed spindles that the primary space is on.

]]>