- Community Home
- >
- Servers and Operating Systems
- >
- Operating System - Linux
- >
- General
- >
- for speed, should I also use 'bs' in 'dd' ?
-
- Forums
-
- Advancing Life & Work
- Advantage EX
- Alliances
- Around the Storage Block
- HPE Ezmeral: Uncut
- OEM Solutions
- Servers & Systems: The Right Compute
- Tech Insights
- The Cloud Experience Everywhere
- HPE Blog, Austria, Germany & Switzerland
- Blog HPE, France
- HPE Blog, Italy
- HPE Blog, Japan
- HPE Blog, Middle East
- HPE Blog, Latin America
- HPE Blog, Russia
- HPE Blog, Saudi Arabia
- HPE Blog, South Africa
- HPE Blog, UK & Ireland
-
Blogs
- Advancing Life & Work
- Advantage EX
- Alliances
- Around the Storage Block
- HPE Blog, Latin America
- HPE Blog, Middle East
- HPE Blog, Saudi Arabia
- HPE Blog, South Africa
- HPE Blog, UK & Ireland
- HPE Ezmeral: Uncut
- OEM Solutions
- Servers & Systems: The Right Compute
- Tech Insights
- The Cloud Experience Everywhere
-
Information
- Community
- Welcome
- Getting Started
- FAQ
- Ranking Overview
- Rules of Participation
- Tips and Tricks
- Resources
- Announcements
- Email us
- Feedback
- Information Libraries
- Integrated Systems
- Networking
- Servers
- Storage
- Other HPE Sites
- Support Center
- Aruba Airheads Community
- Enterprise.nxt
- HPE Dev Community
- Cloud28+ Community
- Marketplace
-
Forums
-
Blogs
-
Information
-
English
- Subscribe to RSS Feed
- Mark Topic as New
- Mark Topic as Read
- Float this Topic for Current User
- Bookmark
- Subscribe
- Printer Friendly Page
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Email to a Friend
- Report Inappropriate Content
04-12-2009 10:50 AM
04-12-2009 10:50 AM
i use to take backup of /dev/sda onto /dev/sdb, as following
dd if=/dev/sda of=/dev/sdb
should I also use 'bs' ?
if yes then what value for 'bs' is good
Note: I have two system groups, one has both(sda,sdb) disk scsi, and the group has both disk sata
Regards
Maaz
Solved! Go to Solution.
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Email to a Friend
- Report Inappropriate Content
04-12-2009 05:59 PM
04-12-2009 05:59 PM
SolutionDo test of some data and take the time, for example:
time dd if=/dev/sda of=/dev/sdb bs=256k count=100
And compare them with different block sized.
Another thing to consider is that probably you could use another tool to "image" your disk, avoiding the copy of unused disk space.
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Email to a Friend
- Report Inappropriate Content
04-12-2009 09:57 PM
04-12-2009 09:57 PM
Re: for speed, should I also use 'bs' in 'dd' ?
bs, blocksize does improve or degrade performance in dd read/writes.
The value for best speed depends on the layout of the disk itself, which varies based on the OS and the size of the disk.
If you are using LVM, you can obtain information on this and set your size with pvdisplay data.
Now I've said it can improve performance, its not always necessarily going to be dramatic and therefore worth your time.
SEP
Owner of ISN Corporation
http://isnamerica.com
http://hpuxconsulting.com
Sponsor: http://hpux.ws
Twitter: http://twitter.com/hpuxlinux
Founder http://newdatacloud.com
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Email to a Friend
- Report Inappropriate Content
04-13-2009 02:27 AM
04-13-2009 02:27 AM
Re: for speed, should I also use 'bs' in 'dd' ?
http://www.softpanorama.org/Tools/dd.shtml
enjoy life.
Jean-Pierre Huc
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Email to a Friend
- Report Inappropriate Content
04-14-2009 11:17 PM
04-14-2009 11:17 PM
Re: for speed, should I also use 'bs' in 'dd' ?
>If you are using LVM, you can obtain
>information on this and set your size with
>pvdisplay data.
elaborate/explain please
Hewlett Packard Enterprise International
- Communities
- HPE Blogs and Forum
© Copyright 2021 Hewlett Packard Enterprise Development LP