Every sysadmin that has upgraded or patched a system running multiples zones will tell it, the upgrade was an undefinably long process.
When you consider that some SPARC machines are running now with 256 threads, it’s a shame that such boxes are upgrading with a single thread (each zone sequentially, I mean). This is the end of a long wait ! SUN releases today patches that introduces parallel patching of zones.
It seems that we just need to apply 119254-66 (SPARC) or 119255-66 (x86) patche to take benefit from this feature. After the patchadd, just set the number of zones that should be patched in parallel by editing the file /etc/patch/pdo.conf and sets the value of num_proc var.
Happy (live) patching!