Recently I burned a copy of OpenSolaris 2008.11 RC1 and used it with Songbird (using pkg install SUNWsongbird) and Fluendo MP3 Decoder (which is free for OpenSolaris), Flash and soon I had a setup in my bedroom which I love to call OpenSolaris Home Theatre Edition that I used to listen to my songs collection and watch online shows that I controlled via Remote Desktop which to me was a serious contender to those Media Centers out there.
However I realized that while I wanted to "Pump it up" for my personal usage, I really wanted to "Strip it Down" for business usage. What I meant is in order for someone to try it out with say another Open Source Software it is easier now to say try that Open Source Software pre-installed on OpenSolaris in a Virtualbox Image. However I found it very hard to do it in practice.
Say for example I want to get somebody to try out the latest version of MySQL on OpenSolaris. The easiest thing is to give them a VDI image of preinstalled version of MySQL 5.1 RC running on OpenSolaris that somebody just double clicks and boom a virutalbox instance starts up with MySQL ready to deliver.
However there is a problem with that theory. The VDI image of OpenSolaris fresh install in a virtualbox instance is about 2.5 - 3 GB. Of course adding MySQL on top of it won't drastically increase the size but I still have a problem with the base size itself. Since the only way that this can work is to use some sort of Peer to Peer File Sharing technology as hosting and hoping people will download this DVD Size downloads without any problems is like going at 10:00am for a Thanksgiving Deal at a store that opens at 6:00am with less than 20 SKU available (Tough Luck!!).
Anyway I started dissecting on how to reduce the size of the VDI image. There are few tricks provided by Virtualbox itself to release zero'ed out sectors using
VBoxManage modifyvdi VDINAME compact
However trying this out on a VDI holding OpenSolaris 2008.11 RC1 candidate did not really help.
The next thing I tried was to list out all the packages that are installed using
There are about 550 packages installed as reported by that list. I tried removing many of the non-essential desktop things (Aha who needs Xorg, Gnome, Firefox, Thunderbird) and reduced it to less than 400 packages. However even with that the VDI images is still not much smaller than 2.5GB. I tried the trick of cloning the disk to another VDI via ZFS replace thinking it will get rid of all the freed up space obtained by removing all the packages but the resulting new VDI image was still 2.5GB.
Looking at ZFS list output I found that for my virtualbox instance with 512MB I have three main zfs file systems defined which gives me the approximate 2.5GB usage.
rpool/ROOT/opensolaris- The legacy mount which is root (/) which is about 1.3 GB
rpool/dump which is about 512MB
rpool/swap which is again about 512MB
Now the goal is to reduce the VDI size without creating complications for the end user trying out the VDI and also still have the capability of going back to the fully installed version of OpenSolaris.
Hence the quest still continues..