jmacd / xdelta

open-source binary diff, delta/differential compression tools, VCDIFF/RFC 3284 delta compression
http://xdelta.org
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Unusable output with custome input window. #13

Closed GoogleCodeExporter closed 9 years ago

GoogleCodeExporter commented 9 years ago
What steps will reproduce the problem?
1. run xdelta with the input window set to 64mb
2. attempt to restore the target

What is the expected output? What do you see instead?
Expected: a restored target.
Instead: error message - xdelta3: hard window size exceeded: XD3_INTERNAL

What version of the product are you using? On what operating system?
3.0k on windows xp pro

Please provide any additional information below.

xdelta didn't indicate any problems while creating the output.
source window size was left to default.
its likely this error repeat with other/any custom input window size,
i've gotten it with values both larger and smaller.

Original issue reported on code.google.com by H.Re...@gmail.com on 13 Jan 2007 at 5:29

GoogleCodeExporter commented 9 years ago
It doesn't make sense to set the input window (-W) to 64MB--it won't improve
compression compared to a smaller window (the default is 256KB).  The source 
window
(-B) should be larger for large inputs, not the input window.

There is a hard-coded limit in the decoder, which I think I will remove to 
avoid this
kind of confusion.

Original comment by josh.mac...@gmail.com on 13 Jan 2007 at 11:48

GoogleCodeExporter commented 9 years ago
actualy if you could spare the time and put a small explanation about xdelta's 
work 
proccess and what settings have what effect in the wiki it'll probably be for 
the 
best, as it is some things are pretty hard to figure out.

Original comment by HellRe...@gmail.com on 14 Jan 2007 at 1:16

GoogleCodeExporter commented 9 years ago
The -W setting (for input window size) is now limited in the same way the 
decoder
limits it, although I admit this is still somewhat of a problem, since a foreign
encoder could produce such a delta.

I've tried to explain the -W setting in
http://code.google.com/p/xdelta/wiki/TuningMemoryBudget

Thanks.

Original comment by dotdotis...@gmail.com on 16 Jan 2007 at 3:16

GoogleCodeExporter commented 9 years ago

Original comment by dotdotis...@gmail.com on 16 Jan 2007 at 3:17