Difference between revisions of "Compressed printk messages"

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(Created page with "; Summary: Compressed printk messages ; Proposer: Tim Bird - Sony Network Entertainment == Description == Attempts have been made in the past to compress printk messages to save...")
 
(add some miscelaenous issues)
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; Summary: Compressed printk messages
 
; Summary: Compressed printk messages
; Proposer: Tim Bird - Sony Network Entertainment
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; Proposer: Tim Bird - Sony Mobile Communications
  
 
== Description ==
 
== Description ==
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to automatically (at compile-time) compress the kernel's printk messages,
 
to automatically (at compile-time) compress the kernel's printk messages,
 
and transparently expand them at runtime.
 
and transparently expand them at runtime.
 +
 +
The goal would be to no user-visible change in behaviour for the
 +
kernel, as well as no required developer-visible changes in the source code.
 +
Probably, a new kernel option would be used to control this
 +
feature.
 +
 +
The work would involve parsing the kernel source code, extracting
 +
the messages (and possibly replacing them in source, during the compilation).
 +
 +
=== Miscelaneous issues ===
 +
There may be an issue with finding all kernel messages, due to the number
 +
of macros (probably in the hundreds) that are used to wrap printks.
 +
This feature might still be useful, even if not all kernel messages
 +
could be converted, as long as significant size savings were made
 +
available by using the feature. Significant size savings would be
 +
on the order of 50K to 100K.
 +
 +
There might also be some benefit from message consolidation.  (I don't know
 +
if the compiler already coalesces identical strings, but this system should
 +
be able to.)
  
 
== Related work ==
 
== Related work ==
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== Scope ==
 
== Scope ==
Unknown - 2-4 weeks?
+
Unknown - 4 to 8 weeks?
  
 
== Contractor Candidates ==
 
== Contractor Candidates ==
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== Comments ==
 
== Comments ==
 
+
This project was proposed in 2012, but not sponsored that year.
  
 
[[Category:Project proposals 2012]]
 
[[Category:Project proposals 2012]]
 +
[[Category:Project proposals 2013]]

Revision as of 17:25, 1 October 2013

Summary
Compressed printk messages
Proposer
Tim Bird - Sony Mobile Communications

Description

Attempts have been made in the past to compress printk messages to save kernel runtime footprint. There is an option to disable all printks, but many embedded developers do not use it, even when they find the space savings attractive, because they still would like to see kernel debug messages.

This project would consist of researching mechanisms that could be used to automatically (at compile-time) compress the kernel's printk messages, and transparently expand them at runtime.

The goal would be to no user-visible change in behaviour for the kernel, as well as no required developer-visible changes in the source code. Probably, a new kernel option would be used to control this feature.

The work would involve parsing the kernel source code, extracting the messages (and possibly replacing them in source, during the compilation).

Miscelaneous issues

There may be an issue with finding all kernel messages, due to the number of macros (probably in the hundreds) that are used to wrap printks. This feature might still be useful, even if not all kernel messages could be converted, as long as significant size savings were made available by using the feature. Significant size savings would be on the order of 50K to 100K.

There might also be some benefit from message consolidation. (I don't know if the compiler already coalesces identical strings, but this system should be able to.)

Related work

Scope

Unknown - 4 to 8 weeks?

Contractor Candidates

None yet.

Comments

This project was proposed in 2012, but not sponsored that year.