Utilizing multi core for tar+gzip/bzip compression/decompression

Hi,

I normally compress using tar zcvf and decompress using tar zxvf (using gzip due to habit). I've recently gotten a quad core CPU with hyperthreading, so have 8 logical cores, and I notice that many of the cores are unused during compression/decompression. Is there any way I can utilize the unused cores to make it faster?

Thanks.

Yes, there is.
Use pigz - Parallel gzip

pigz is nice but gzip as sometimes used because of the time it took to bzip2 it.
I've been using pbzip2 and it saves a lot of time.

compression.ca/pbzip2