Parallel portupgrades

[Dmitry Marakasov]

Hi!

I remember launching multiple portupgrades in parallel once broket my
pkgdb. Bit that was long time ago, and now I wonder if there was
any locking introduced so I may launch multiple parallel portupgrades.
I thing I saw this feature in portupgrade's TODO on wiki, but I'm
unaware of it's current status.

-- 
Best regards,
  Dmitry Marakasov               mailto:amdmi3 at amdmi3.ru