Hi,

How to compress a single file of 2GB size so that I can reduce it in a most possible smaller size. I used some of the commands like:

#tar -cvf filename.tar.bz2 filename

and it reduces that 2GB file in 859MB filesize.

With gzip you can try using -9 or --best options for "best compression."

With bzip2 you can try those same options and/or --repetitive-best.

Compression tends to depend upon content and these command line options may or may not be of benefit -- it's a try it and see sort of thing.

Hope this helps some.

1 members found this post helpful.

That is the correct command to use, to compress a file.

However, sometimes, depending on the contents of the file, it won't compress very efficiently. Some types of data are very repetitive, and therefore will compress very well, to a much smaller size. Data that is not very repetitive, such as images (jpgs are already inherently compressed), recorded sound, or just plain random data, don't compress very well.

Data that is highly repetitive, such as a simple text document, or log file, or even structured data files, such as database files, will compress very well. simple text files can often compress down to 10-15% of the original size.

Without knowing what data you are trying to compress, i would say that 2G compressing down to 850ish MB is pretty decent for mixed data.

-Matt

It is a single database file of 2GB and yeah I know 850MB is good but I was wondering if there is any other method to bring it's size more less..

Use xz compression:

Or for absolutely max compression:

you can try also 7zip to see if size will be smaller

good luck

1 members found this post helpful.

When I tried this format : on my server:

it gave above output.
Was there something wrong I did?

May be a missing package xz : # apt-get install xz / # yum install xz

It's a single file (not a directory)? If so, try one of the options I gave you; e.g.,
See what that does for you; also try the other options and see what they do. You'll wind up with 2gifile.bz2.

If it's a single file, there really isn't much use in making a tar archive; I mean, you know where it was so you know where to bunzip2 it if you need it back, eh?

If you don't have the XZ utilities, you can find them at http://tukaani.org/xz or, perhaps, your distribution software site.

Hope this helps some.

What you have already achieved is pretty darned good. Call it "good enuf," and move along.

See this.
PAQ8px -7

http://www.maximumcompression.com/data/summary_mf.php