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Bug 160319 - Enable O_DIRECT in dd
Summary: Enable O_DIRECT in dd
Alias: None
Product: Red Hat Enterprise Linux 4
Classification: Red Hat
Component: kernel
Version: 4.0
Hardware: All
OS: Linux
Target Milestone: ---
: ---
Assignee: dff
QA Contact: dff
Whiteboard: None
Depends On:
TreeView+ depends on / blocked
Reported: 2005-06-14 12:52 UTC by Stephen Tweedie
Modified: 2012-06-20 15:54 UTC (History)
0 users

Fixed In Version:
Doc Type: Bug Fix
Doc Text:
Clone Of:
Last Closed: 2012-06-20 15:54:43 UTC
Target Upstream Version:

Attachments (Terms of Use)

Description Stephen Tweedie 2005-06-14 12:52:58 UTC
Description of problem:

Raw devices are deprecated.  The recommended way of achieving the same
functionality is to open a regular block device with O_DIRECT.

But customers cannot completely migrate to O_DIRECT as long as certain core
tools, often used on raw devices, do not support O_DIRECT.  In particular, dd is
often used to copy/backup raw device contents; it needs to support O_DIRECT to
enable this migration.  

The severity of lacking O_DIRECT is mitigated by the fact that buffered IO
_does_ still work; it's just less efficient, both in terms of CPU utilisation
and the load it places on the VM.

Comment 3 Jiri Pallich 2012-06-20 15:54:43 UTC
Thank you for submitting this issue for consideration in Red Hat Enterprise Linux. The release for which you requested us to review is now End of Life. 
Please See

If you would like Red Hat to re-consider your feature request for an active release, please re-open the request via appropriate support channels and provide additional supporting details about the importance of this issue.

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