How to open big tar.gz file

Question

I created a big tar.gz file, following this guide. It is a daily backup file.

My computer has 3 GB of RAM and is running Windows 7. My biggest archive is 183 GB, containing pictures and documents.

The backup is quite useless since I can't open it and extract. Every time I try, my computer always runs out of memory (using 7-zip).

Has anybody had the same problems?

Solution 1

You need to open the file using something that reads and processes it as a stream, rather than trying to read the whole file into memory.

Try installing Cygwin and managing the file using its command-line tools; for example

$ tar zxf my-big-file.tar.gz something/I/want.doc

will extract one file from your archive.

As a Unix guy, naturally I offer a Unix-like solution :-)

Solution 2

Cygwin - as sugested - is an overkill. You can try to use http://tartool.codeplex.com/ which is a commandline tool and doesn't require installation (just unzip).

Then you can addapt suggested command:

tar xzf backup.tar.gz folder/file_you_want.txt

x - extract
z - compressed with GZ
f - file to extract

To work with tartool:

TarTool.exe backup.tar.gz /destination/

Unfortunately tartool doesn't allow to pick which file you want.

Comments

[gronostaj]

Does it run out of RAM or disk space? What is the error message?

[Jonathan Ben-Avraham]

Installing Cygwin can be daunting for Windows users. An alternative would be to boot from a Linux LiveCD and run the tar command in that environment, no need to install anything that way. An alternate command in the Linux environment would be zcat my-big-file.tar.gz | tar xvf - something/I/want.doc. You can do zcat my-big-file.tar.gz | tar tvf - | more to list the files and see the correct path names first.

[Ramhound]

@JonathanBen-Avraham - Its only daunting if you don't read the instructions.

[FSMaxB]

Cygwin is not required. Tar is available via the GNU Win32 project gnuwin32.sourceforge.net/packages.html.

[SeriousLee]

Okay but what if you need to extract the entire large file? Or how would one see the directory of the tar so that you can figure out the directory of the one file you want to extract?