Showing posts with label production. Show all posts
Showing posts with label production. Show all posts

Thursday, 12 July 2012

Making Agile Go Fast

Just recently I was speaking with a potential customer who had concerns about the velocity of their Scrum teams. They had recently (9 months ago) switched to an agile approach and had expected to get much more delivered than they had.

Now they were looking in to scaling up the number of Scrum teams on the project to try and increase velocity and deliver more quickly. In my experience of many agile projects, increasing the number of people on the project, especially one that is struggling, never has the desired effect of making things go faster. The advice to this customer was to therefore look at making their existing teams and process more effective rather than increasing the number of people on the project.

This got me thinking about what makes agile projects go slow. Across a number of projects that I have experienced, I’ve identified four common traits: two related to people and process and two related to technical concerns.

The Wrong People

Agile is all about using the right people. In fact this is true for any project or process, but for agile it is even more important. Use the right people and the agile process will work. Use the wrong ones and you will struggle.

The people who you don’t want on your agile project are those who are not disciplined enough to follow sound engineering practices and those who try to build complex frameworks/toolkits and who conduct personal science projects on your codebase. If you want to go fast then it’s vital that you have a clean, simple and well-refactored codebase that is backed up by a set of quality tests. Team members who don’t support this vision slow down the whole team.

To get back on track, remove those devs who aren’t following good engineering discipline and those who keep making things more complex. Bring in experienced agile developers to pair with the remaining team, giving them the responsibility of ensuring quality engineering practices are followed.

Putting The Process First

Another common mistake of companies starting out with agile projects is that they assume the process will make them go faster. Sorry to disappoint, but this is just not true. What makes agile teams go fast is creating open channels of communication and self organising and empowered teams.

If an organisation can’t create an excellent environment for communicating then no agile process will help. Agile helps teams go faster by eliminating the unnecessary documentation and waterfall steps. However, this information transfer must still happen and it happens through closer communication and collaboration.

Sadly, many organisations create agile teams and give them a process to follow but then insist on telling them how to organise, what tools and techniques to use, how to work and exactly what to do. This isn’t agile, it’s just another way of organising a traditional team. If you want agile to go fast then the team need total control over how they work and what they do.

To get back on track from here, relax on the process. Work on increasing communications. Give the agile teams the chance to decide how they will organise and work. Give them control and they will go faster. Agile is not a process, it’s about letting people get the job done.

Using The Wrong Technologies

So many agile projects struggle because they are using the wrong technologies. When this is the case it’s usually because the technology approach has been foisted on the team by an ‘ivory-tower’ architect or some senior manager who was wooed by the sales consultant from a large vendor. In other cases it may be that the team are forced into using a ‘corporate standard’ technology set.

In many cases the team will repeatedly identify the technology as a major factor in retrospectives. However, more often than not they will be told that this is not something that can be changed and that they have to stick with it. Why throw away hundreds of thousands or even millions on staff costs when backtracking on some poor technology choices would make so much difference.

Again, giving the teams the authority to make technology decisions is essential. Allowing technology choices to be reversed if they prove to be hindering delivery is also an important part of being agile.

Making The Architecture Too Complex

Many software systems are designed, or become, far too complex. In an agile environment this is a guaranteed way of making things go slower. Software must be kept as simple as possible so that it is easy to continually change and enhance.

If the architecture of an agile system has become so complex that it hinders development then it must be revisited and greatly simplified. Layers must be removed, interfaces reduced and code and technologies radically refactored to make everything simpler. Once that is done then the project must work all out on stopping it from getting more complex again in the future.


Only by using the right people, correctly empowered and communicating can the team have the ability to go fast and be truly agile. Only by making the correct technology choices, reversing bad technology choices and keeping everything simple can the ability to turned into real agile delivery.

Wednesday, 17 November 2010

Why Releases Should be Automated and Environments Equivalent

Last weekend I was involved in a fairly major release for one of my customers. Ultimately we were unable to complete the release due to a number of factors (some within our control and others outside). However, the release was still deemed successful as we were able to cleanly abort and rollback to the previous working version with an absolutely minimal service outage. The release did however highlight a number of places where the release process could be improved.
So, where did this release go wrong. There were three main problems that were encountered:
  • A switch failure in one of the data centres that temporarily rendered some servers inaccessible.
  • Mistakes in the manual actions in the release plan.
  • A data inconsistency between two different data centres.

Unexpected Events During a Release

Murphy's Law: Anything that can go wrong, will go wrong.
Unfortunately, no matter how well you plan, there will always be things that you can't anticipate. In this particular release we had a hardware switch fail right in the middle of the release. An erroneous configuration in the data centre caused this failure to render a number of our servers unreachable. We were therefore mid-release with no way to go forward and an arduous rollback process to restore us back to a working state.
Fortunately due to diligent disaster recovery work undertaken previously we were able to fail the entire site over to the alternative data centre. A pragmatic decision was eventually taken that we couldn't wait on the chance that we MIGHT be able to complete the release so we rolled back. This was well planned and went smoothly enough that within 30 minutes of a new switch coming online we were back up and running on the original software versions. Nice work.
However, even flushed with the success of our miraculous escape from the clutches of Murphy, we have to consider what might have been. Our rollback was a largely manual process and although tested in the test environment, our production is just different enough as to add a level of uncertainty to the rollback process. There's also the greater chance of errors in manual steps when under pressure of a live situation.
So how could we be more certain of our rollback plan?

Untested Manual Release Plans

Our release had a very detailed plan that had been well reviewed before hand. A variation of the plan had been executed in test but, as I already said, the production environment is just different enough as to require a different (and slightly more complex) plan. Additionally, this release had some additional complexities requiring a number of extra manual steps.
What we discovered during the release was that some of the steps specific to production were in fact not quite correct. Couple this with the chance of making errors when executing manual steps and we have a number of places with a high potential for failure.
While the plan did run pretty smoothly, how could we reduce the chances of errors and mistakes?

Problems That Can't be Found Before Production

The final problem encountered on the release was one of database consistency. Database in two different data centres were thought to be consistent. It turns out they were not! With hindsight, we should have checked this and have been continually monitoring these over time. We live and learn.
What should really have happened is that we detected the possibility of inconsistent databases before we got to production. Unfortunately all the lower environments only have a single data centre model for the database in question so there was no way that anything could ever get out of sync in those cases. Hence, no way to detect the problem before reaching production.
How can we find these sorts of problems earlier?

Automate Releases, Equivalent Environments

Fortunately, all of the above problems can be fixed with two solutions. I wanted to say SIMPLE solutions, but unfortunately they are not particularly simple and require a fair amount of work to get right. These solutions are:
  1. Automate the release and rollback pipelines.
  2. Ensure Integration and Test environments are identical equivalent to Production.
Automated Releases
In a modern computing environment there is really no need to include manual steps in a release. Even when releases have lots of complexity it should be possible to script all the required steps. An automated script can be tested, fixed and re-tested many times in order to ensure it is correct before running it against a production environment. This is much better than a manual process that is difficult to test and open to human error.
Don't get me wrong, creating automated releases is hard, but the benefit of smoother, faster and more frequent releases to production gives significant enough business benefit to make the effort worthwhile.
Equivalent Environments
A manufacturer building a product wouldn't create a prototype and then go straight into mass production with a design that varied significantly from that prototype. Companies building software shouldn't do so either. The purpose of Continuous Integration is to find problems early when they are quicker and cheaper to fix. In order to work well, the lower environments need to match production in terms of applications, server structure, configuration and so on.
Additionally, if we are to build automated deployment plans then we need production like environments to develop and test them against. An unproven automated plan is of no more value than a fully manual one.

Conclusions

By automating releases and having equivalent environments we give ourself the best possible chance of undertaking regular, successful and stress-free releases. When Murphy does come along, knowing we have an automated way to get back to a working system saves a whole lot of worry and stress. Yes, it's hard to get to this point, but the long term benefit to a business from doing so is worth every penny and every hour spent.