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Improve handlig of (bigger) delta blocks on Windows platform #5

Closed GoogleCodeExporter closed 9 years ago

GoogleCodeExporter commented 9 years ago 
What steps will reproduce the problem?
1. No direct issue, just a suggestion of improvement
2.
3.

What is the expected output? What do you see instead?

Using this nice utility on the Windows platform I like to suggest improve 
handlig of bigger delta blocks, by default. I use it as a command line 
utility. When using Xdelta on huge (several GByte) files, I find it OK to 
allocate more RAM.

What version of the product are you using? On what operating system?

xdelta30i.x86-32.exe

Please provide any additional information below.

In xdelta.h I suggest this change:

48c48,52
< #define XD3_DEFAULT_SRCWINSZ (1U << 23)

---
>   #ifndef XD3_USE_LARGEFILE64
>     #define XD3_DEFAULT_SRCWINSZ (1U << 23)
>   #else
>     #define XD3_DEFAULT_SRCWINSZ (1U << 26)
>   #endif

Original issue reported on code.google.com by fib.denm...@gmail.com on 17 Dec 2006 at 4:01

GoogleCodeExporter commented 9 years ago 
I agree there is a need to automatically size memory use. For now, you should 
get the
same effect by setting -B 67108864

Original comment by dotdotis...@gmail.com on 18 Dec 2006 at 4:29

GoogleCodeExporter commented 9 years ago 
Automatically memory sizing would be nice. -B (or recompile) will do in my 
case. 
Thanks

Original comment by fib.denm...@gmail.com on 21 Dec 2006 at 11:15

GoogleCodeExporter commented 9 years ago 
Other than the souruce, is there a description somewhere of the effects 
window/block/hastable size has on compression? I was tinkering with these a 
bit, but 
I cannot make sense of them.

What I would really like is to achieve rsync-like behavior: block matches from 
the 
whole file are considered. I am not certain that is happening now (I have seen 
some 
big diff files for small changes that are still bigger than a single block).

Original comment by malay...@gmail.com on 4 Jan 2007 at 10:54

GoogleCodeExporter commented 9 years ago 
The default for -B is now 64MB (1<<26). Thanks. :-)

Original comment by josh.mac...@gmail.com on 13 Jan 2007 at 2:15