I wondered how little we can actually install as a starting point for building a minimised system. The new IPS package system makes this much easier and makes it work in a supportable way without all the pit falls of patches and packages we had previously.
For Solaris 11 I believe the currently smallest configuration we recommend is the solaris-small-server group package.
Note the following is not intended to imply this is a supported configuration and is illustrative only of a short amount of investigative work.
First lets look at a zone (it is easier since there are no driver issues to deal with):
I discovered it is possible to get a 'working' zone by choosing a single package to install in the zone AI manifest and that package is:pkg:/package/pkg
That resulted in 175M being reported as being transferred by pkg. Which results in 255M on disk of which about 55M is /var/pkg. I had 140 'real' packages (ie excluding the incorporations).
We have 71 online SMF services (nothing in maintenance) with 96 known SMF services.
Around 23 processes are running (excluding the ps I used to check this and the shell I was logged in on).
I have discovered some potential packaging that could result in this being a little bit smaller but not much unless a break up of pkg:/system/core-os was done.
Now onto the bare metal install case.
This was a little harder and I've not gotten it to where I wanted yet.
Ignoring drivers the only thing I needed on an x86 system was:pkg:/package/pkg and pkg:/system/boot/grub
Which is good and not really different from the zones case.
However that won't produce a bootable system - even though it produces one that will install!
To get it to boot I took the list of all the network and storage drivers from the solaris-small-server group package. I removed all the wlan drivers and also any drivers I knew to be SPARC only. My list of packages in the AI manifest had 113 driver packages in it.
That got me a bootable system, though not one minimized with respect to drivers.
We have a few more processes in the global zone (again ignoring the ps and my shell) this time I counted 32. This came from 89 online services. Again ignoring the incorporation packages I had 161 packages installed of which 73 were in the pkg:/driver namespace.
The disk space footprint is much bigger at total of 730M - but remember I've likely installed drivers that I might not need.
This time /var/pkg is 174M of that.