A while ago I posted a note about the success Virgin mobile experienced from switching to a Space-Based Architecture.
I received a comment from Julian Browne that I think is informative and so I make it public here:
Hi Owen – a backend system was unavailable for a few hours (honestly I
can’t remember the exact time). It was towards the end of the day’s
activity and it wasn’t back online until after midnight.
We knew this because one of the business managers thought they spotted
a bug in our reporting software after it informed him that more than
100% of orders had just been fulfilled. Never having seen anything
more than a 100% fulfilment rate, he naturally suspected an error.
On investigation we discovered that some of the previous day’s late
orders had been held in the space until the legacy system came back up
and submitted to the warehouse that morning. The system that was
replaced by the space-based approach didn’t do this and would often
lose orders entirely. What he really loved about this was that
managing orders safely in the event of a backend system not being
ready hadn’t even on his list of requirements.
I think there’s been some confusion created by other posts about the
project around order numbers generally. The number of online orders
increased by around three times almost immediately we went live (IT
wasn’t aware of this for a while, the system just scaled up without
any complaint) and over the Christmas period (a stressful time under
the pre-SBA solution) we handled a massive increase in orders
completed (unfortunately I’m not at liberty to say by how much because
it’s commercially sensitive).
I spoke to the online director only a couple of weeks ago and he still
loves it nearly two years later.
It is great to know that what was once only a few lines of test code has survived and blossomed into a reference implementation.