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danswano
26-07-2017, 01:18
Hello,
Should i consider switching to external lzma2 instead of internal lzma for better compression ratio?
What do you suggest to get the best ratio out of lzma?

FitGirl
26-07-2017, 03:33
LZMA2 usually have worster compression ratio than LZMA1, but can be faster due to saving of uncompressible blocks as is.

Chayan Manna
27-07-2017, 03:17
You can better the compression ratio with LZMA 1 by increasing the RAM usage. That is like "d512" parameter. Increase the value of "d" ( that memory is needed to decompress) & you will get better ratio, of course other parameters must be set correctly. Decompression will be faster also but will use more RAM.

danswano
27-07-2017, 05:18
I'm using these parameters and i can't seems to get a better compression ratio out of it no matter what i adjust
"lzma:a1:mfbt4:d180m:fb273:mc10000:lc8"
what's the better version of these parameters would be as you suggest?

shazzla
27-07-2017, 05:50
imho its the best.
increase d180m to d1024m if you have enought RAM.

doofoo24
27-07-2017, 06:05
I'm using these parameters and i can't seems to get a better compression ratio out of it no matter what i adjust
"lzma:a1:mfbt4:d180m:fb273:mc10000:lc8"
what's the better version of these parameters would be as you suggest?

you need to use fazip 64x for lzma beyond d184mb because lzma built-in freearc is limited..

[External compressor:mm,dispack070,rep,tor,delta,4x4,lzma]
header = 0
packcmd = fazip -i0 compress:{compressor}{:option} <stdin> <stdout>

ChronoCross
27-07-2017, 06:26
First at all internal arc LZMA is 32bit so you have a memory limitation thats why lzma_x64 was created you can use 4gb of memory the same thing with srep x64. external x64 always is better than internal x86.(fazip_x64 is the best !!!!)
LZMA and LZMA2 are different.
LZMA Better for compression ratio.
LZMA2 Better for time decompression .

LuzhinE
27-07-2017, 09:15
ChronoCross:

Then how would the parameters for fazip and srep X64 to use 4gb decompression

ChronoCross
27-07-2017, 09:48
I think you confused, 4gb in decompression is a requirement and not an optimization.
The optimization would be to limit the memory to decompress.
This would be during the compression in freearc "-ld512".
You can use 4gb for compress and then 512mb to decompress.

1234567890123
28-07-2017, 00:11
can someone give fazip x64 i haven't found it in freearc's site is broken and is there x64 arc.exe ?

Chayan Manna
28-07-2017, 01:40
can someone give fazip x64 i haven't found it in freearc's site is broken and is there x64 arc.exe ?

Here's Fazipx64. :)

LuzhinE
01-08-2017, 17:44
I used this parameter and it works.
lzma:a1:mfbt4:d180m:fb273:mc10000:lc8

But change d180m by :d256m and it takes longer to compress, but compresses a little more.

My question is, how do I use my cpu 100% because in the image it is only seen that it uses 50% when compressing

http://i.imgur.com/Bp6Udt6g.png

Simorq
02-08-2017, 01:42
I used this parameter and it works.
lzma:a1:mfbt4:d180m:fb273:mc10000:lc8

But change d180m by :d256m and it takes longer to compress, but compresses a little more.

My question is, how do I use my cpu 100% because in the image it is only seen that it uses 50% when compressing

http://i.imgur.com/Bp6Udt6g.png

[External compressor:rep,mm,delta,exe,exe2,4x4,lzma]
header = 0
packcmd = FAZip64 -i0 compress:{compressor}{:option} <stdin> <stdout>
unpackcmd = FAZip64 -i0 decompress:{compressor}{:option} <stdin> <stdout>

4x4:lzma: a1: mfbt4: d180m: fb273: mc10000: lc8
But the more RAM