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Subject: Re: [Drbd-dev] Compression in DRBD
From: komal <komal@linsyssoft.com>
To: Philipp Reisner <philipp.reisner@linbit.com>
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Date: Wed, 07 Mar 2007 18:18:08 +0530
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On Wed, 2007-03-07 at 12:55 +0100, Philipp Reisner wrote:
> Am Mittwoch, 7. März 2007 11:16 schrieb komal:
> > Hi all,
> >           Bandwidth is an important issue in DRBD during replication of
> > data. If bandwidth is properly utilized then replication will be faster
> > and speed is what everyone needs.
> >         When bandwidth utilization comes into picture, compressing data
> > is what
> > is needed. Earlier discussions were going on to use vtun with a tcp
> > tunnel with zlib compression factor 9 or so to achieve compression.
> >         What about implementing compression in DRBD itself. Like using
> > zlib to
> > compress each packet and decompress it on receiver side in DRBD code
> > itself rather than using vtun and all. Wont it solve the purpose?
> >
> 
> Hi,
> 
> DRBD is a really complex piece of software, and I really do not want to
> duplicate anything that can get achieved on other levels.
> 
> Compression on the network can for sure be achieved by other means 
> (outside of DRBD).
> 
> -phil

Hi,

	But if we implement compression in DRBD itself we can have selective
compression. 
	By selective compression I mean is that we will compress only data
packets and not configuration packets (which reports status and
configuration) which cannot be achieved with other compression
techniques. 
	
Thanks and Regards,
Komal