Solved

seperate drives for data-log even in VM envonrment

Posted on 2011-09-19
5
270 Views
Last Modified: 2012-05-12
in physical server for SQL Server database implementation, it is generally recommended to have data and log in separate drive (with separate spindles?)

is that standard applicable to Virtual servers also?
0
Comment
Question by:25112
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
5 Comments
 
LVL 15

Accepted Solution

by:
Anuj earned 150 total points
ID: 36564774
Yes, you should reside in independent disk, this is applicable to tempdb also. These are best practice recommendation from Microsoft, The following link will help you regarding VMware best practice.
0
 
LVL 14

Assisted Solution

by:Daniel_PL
Daniel_PL earned 150 total points
ID: 36564867
Independent disk (or group of disks e.g. in RAID) means that you should use different physical devices or groups of them for each type of files. This is because log files presents different I/O characteristic than data file(s). Log is written to as sequential unlike data files, which tends to be written in random fashion. In simplistic terms in an OLTP database, your throughput is determined by the speed of writes to the Transaction Log.
0
 
LVL 20

Assisted Solution

by:Marten Rune
Marten Rune earned 150 total points
ID: 36565176
However there is a ongoing discussion about this, the concerns are data security (i e what data is at risk when XXX failes) and performace of the system.

The discussion goes like, if I set up a raid 5 for data, raid 1+0 for system, raid 1+0 for tempdb, raid 1+0 for logfiles and finally a raid 1+0 for indexes.

Will this genereate a faster more redundant environment than:

A Huge raidset perhaps raid6 with 19 spindles?

The above example with raid 5 and raid 1+0 has 19 spindles. The recommendations vary and really you will only know if you test your system, under similar pressure as expected to really know whats the best in every case.

In order to secure data, a raid6 can afford to loose two drives at once and it will still deliver, this is however not the case with the traditionally built system above. If the wrong two drives fail the server stops.

Sooner or later a system thats built on XXX Spindles will outperformance the traditionally built system, and be as secure or even more secure. The question in the debate is how to calculate the magic amount of spindles. This calculation also includes processors/cores, memory, and the behaviour of the system it's designed to support. So as always the answer is, it depends!

Regards Marten
0
 
LVL 5

Assisted Solution

by:VENKAT KOKULLA
VENKAT KOKULLA earned 50 total points
ID: 36573630
The reason the data file (mdf) and log file (ldf) should normally be on separate drives is that when you’re doing inserts/updates/deletes, they both have to write at the exact same time.

It doesn't matter it's a virtual or physical server as i guess...
0
 
LVL 5

Author Comment

by:25112
ID: 36576987
good info
0

Featured Post

Technology Partners: We Want Your Opinion!

We value your feedback.

Take our survey and automatically be enter to win anyone of the following:
Yeti Cooler, Amazon eGift Card, and Movie eGift Card!

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

JSON is being used more and more, besides XML, and you surely wanted to parse the data out into SQL instead of doing it in some Javascript. The below function in SQL Server can do the job for you, returning a quick table with the parsed data.
A Stored Procedure in Microsoft SQL Server is a powerful feature that it can be used to execute the Data Manipulation Language (DML) or Data Definition Language (DDL). Depending on business requirements, a single Stored Procedure can return differe…
Familiarize people with the process of utilizing SQL Server functions from within Microsoft Access. Microsoft Access is a very powerful client/server development tool. One of the SQL Server objects that you can interact with from within Microsoft Ac…
Viewers will learn how to use the INSERT statement to insert data into their tables. It will also introduce the NULL statement, to show them what happens when no value is giving for any given column.

734 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question