Friday 20 December 2013

Debunking the stupid myth that performance is a technical concern

I often hear people saying that latencies and response times are not business topics. I strongly disagree with that vision, and I like the punch-line used by Gojko here: “Debunking the stupid myth that performance is a technical concern”.

Indeed, It’s a fact that extra latencies or bad response times strongly impact the business. As a customer, I can’t stand to wait ages (even minutes;-) until someone (a salesman, a web site,…) is able to answer my questions, or to help me to quickly buy and checkout the product I already identified myself. It’s rather more true nowadays where our expectation level has been dramatically increased with our mobile phone usages.

Asking our business questions like : “what are your objective in term of performance?” is rarely productive. With such approach, we usually end up with average values for our implementation. Clearly the kind of setup fully loaded of implicit, leading to unclear situations,inappropriate architecture choices, and often crisis and strong tensions when we experience fires under production. Sad panda ;-(

On the other hand, by asking our business questions such as “ok, you want an average response time of 1 second, but is it ok for some things to take more than 10 minutes once a day?”, we can start to obtain reactions, deeper involvement, and answers that will  help us to build and validate the service level expectation we need to leverage on.

By leveraging on, I mean: to be verified via a continuous performance test harness, and carefully monitored under production (capacity management). A much more mature way of supporting the business of our clients.

I’d like to end this post with a reference to the excellent presentation of Gil TENE: “How NOT to measure latency”. In particular, Gil is sharing with us the typical kind of questions he asks to his clients in order to establish the performance requirements/service level expectations. 

The outcome of such exercise is something like:
  • 50% better than 20msec
  • 90% better than 50msec
  • 99.9% better than 500msec
  • 100% better than 2 seconds

The entire presentation worth the look, but the typical questions for the interview are showed from the slide #98.

Very useful…

Saturday 14 December 2013

Simple Binary Encoding (SBE): the next protocol buffer?

Even if it's still in beta, the SBE ultra-fast marshalling API (available in C++, Java & .NET) seems very promising. Designed from a financial (FIX Trading community) standard, this first implementation is fully open source, and made by -wait for it ...

  • Martin Thompson (former LMAX CTO) 
  • Todd Montgomery (former 29West CTO)
  • and Olivier Deheurles (for the .NET part)
If you want to discover both the big picture, the history, and how you can use SBE, check the nice post written by my friend Olivier

Another really interesting part to read is the description of the SBE design principles chosen by the authors and published on the SBE wiki. A clearly mechanical sympathy approach ;-)

No doubt this has to be closely followed...

Sunday 8 December 2013

Entreprise Architecture, TOGAF, and the ol' pitfall of big upfront design...

Executive summary:

Entreprise architecture is answering to real concerns & challenges for big-scale companies. After just being TOGAF certified, I don't think that this approach "applied by the book" is the proper answer to support those challenges for any situation where software development is concerned.  Reasons why detailed here (note: allow 27 hours of reading :-)


This week, I followed a training course validated by 2 exams at the end (theory & practice) in order to be TOGAF (9.1) certified. This course, now mandatory for almost every architect in my company, was about Entreprise Architecture (TOGAF stands for The Open Group Architecture Framework).

Wait a minute! What entreprise architecture stands for?

Good question! and as a DDD practitioner, I think it worth here to define our ubiquitous language for the rest of this post. Especially if you are an IT guy like me used to build and deal with softwares, you should not confuse the Entreprise Architect with what you think a Software/Technical Architect is. We are not talking about the same things here... Not at all. You should also not confuse Entreprise Architecture with IT Urbanism here (a kind of autistic & accountable-less french interpretation of Entreprise Architecture as explained by our TOGAF trainer ;-)  

Before defining Entreprise Architecture, TOGAF defines the Entreprise as "any collection of organizations that has a common set of goals". From a TOGAF perspective, an entreprise has a strategy and some capabilities to support this strategy (e.g. to sell its products in EMEA, to produce its products in China, ...). And capability is a keyword here. 

The Entreprise Architecture aims to guide the organizations to identify, specify and assess the changes necessary to execute their strategies. These changes are usually related to the management of their capabilities (did I told you before?). Whether to add a new capability (e.g. to be present on a new market), to change an existing one (e.g. to be compliant with a new regulatory constraint) or to dismantle an existing one (e.g. to stop the production of a given product). 

Of course since "software is eating the world" now, most of these changes will be supported by software development or integration, but having an Entreprise Architecture capability within a company is also important to support non-IT projects like: adding the "capability to build a production factory for our products in Italy in less than 2 years" for instance ... 

Ok. That makes sense to me. This being said, time to talk about TOGAF now.

The TOGAF vision

According to TOGAF, allowing the companies to execute their strategies in an efficient and safe manner is the job of highly skilled people that don't need to have IT knowledge: the Entreprise Architects.

All they have to do, is to leverage on technical experts from various domain to do their job (note from myself: if they think they need to do it...). 

What skills should have Entreprise Architects according to TOGAF? leadership, teamwork, oral and written communications, logical analysis, risk and stakeholders management. Lots of qualities, huh? simply too bad that TOGAF is not mentioning humility, empathy, and continuous learning / improvement mindset...

By the way, I explained the acronym but I didn't explained yet what TOGAF is. TOGAF is a framework including "the methods and tools for assisting in the acceptance, production, use, and maintenance of an entreprise architecture". 

There are 3 main pillars in TOGAF
  1. The Architecture Development Method (ADM) which is a methodology cycle
  2. The Architecture Content framework (describing the needed artefacts) 
  3. The Architecture Capability framework (i.e. the description of what is needed to have an architecture capability within a company, including the governance aspects). 
But ADM is clearly the most important part of this huge document of 633 pages. ADM describes the 10 possible phases (steps and deliverables included) of every architecture project according to TOGAF.

ADM cycle and phases:

What I liked during this training

I must admit that I really enjoyed the introduction of this 5 days course, with statements coming from the (very smart) instructor like: 
  • "Entreprise Architecture considers and supports the entreprise under the angle of its capabilities" (understand: use case driven)
  • "the map is not the territory; we should always stay humble regarding any kind of modeling" 
  • "TOGAF is an Utopia vision, it's mandatory to pragmatically bend this framework to our needs and entreprise's context"
  • "Architects are not here to be simply conceptual: we are here to support people (i.e. our sponsors), and to demonstrate value. We need to deliver! We should not turn ourselves into IT urbanists (i.e. use-case-focusless ivory tower guys ;-)"
  • "we should always know and remind us who we are working for (i.e. the sponsor of the entreprise architecture initiative)"
  • TOGAF favors a "just enough" approach. If what you are doing is not linked to a requirement,  a risk mitigation or an impact. Stop working on it! ;-)
  • The non-testable requirements are not acceptable
  • "Using our veto card means that you've already lost as an architect"
  • "There should be no architect within the entreprise architecture board! Indeed, the entreprise architects aren't the big persons (i.e. the executive decision takers with money). They are simply here to help big persons to take the good decisions regarding the objectives of the company (they've usually defined before)."
But it's important to notice here that most of those statements were coming from the instructor's experience, and not directly from TOGAF itself.

Regarding TOGAF now, I also appreciated that its ADM cycle was requirements-centric. ADM dedicates most of its phases to work on the "architecture" (from phase A to D); architecture meaning here "the description of the requirements to be taken into account". The "solution" arrives quite late in the process (mostly from phase E).

Since It's a common pitfall for everyone to be solution-driven instead of being use-case driven, I was quite pleased to find that mindset in TOGAF.

The 2 last thing I really appreciated within TOGAF, were:
  1. The clear expression of the business/architecture principles (including their implications)
  2. But also the exigences related to a good governance. Including the importance of the transparency of the architecture board decisions (minutes) to all the stakeholders (everyone within the company)

What bothers me within TOGAF? It's clearly not compliant with the agile and continuous delivery approaches...

Not really surprising, since TOGAF was initiated early 1990s. But even if TOGAF indicates that almost all phases of the architectural projects should be executed and reviewed iteratively, I fully disagree with its big upfront design approach. Indeed, TOGAF ADM cycle is basically saying: Entreprise Architects will specify and prepare everything BEFORE the implementation project is launched and transmitted to the involved PMO and dev teams

That doesn't match at all with the agile approach which is saying: confront your vision to the reality and gather feedback on your work as soon as possible... (remember: the map is not the territory...)

All the phases, steps and deliverables indicated within the TOGAF ADM cycle really reminded me the old Unified Process (UP). For those that are too young ;-) UP was the 1990s answer to the major tunnel effect of the former waterfall software methodologies. Ok, UP was far better than the waterfall-based processes, but its bureaucratic pitfall was one of the reasons why the agile manifesto was created at the time (too many deliverables per UP phases and iterations).

Also, the segregation made by TOGAF between the data & application concepts (see phase C) doesn't seem relevant to me. It reminds me the obsolete Merise french method ;-) According to me, considering the data aside the applications' use cases is the best way to fall into the pit of "mini-model the world" anti-pattern. i.e. the kind of situation where people are loosing their time on useless data/topics, simply to improve parts of the model that won't even have usage afterward (on that topic, see the excellent french presentation of Gregory Weinbach). 

There are also some good ideas within TOGAF (most of them are not new), but it clearly doesn't match with today's ways of building IT solutions (whether agile, lean, continuous delivery & lean start-up).

For non-IT needs on the other hand (e.g. "to build a factory from scratch in another country"), TOGAF seems quite applicable & interesting.

But the worst part for me is...

... the caricatural description of the actors involved that you can find within TOGAF (see the matrix presented in the chapter 52.5, or the extract below). Basically, it explains that the Entreprise Architects have all possible skills you can imagine. Even much more skills than the architecture board members (it's probably not the smartest communication move of the open group guys... Cause remember? the Architecture board members are the executive directors of the company that are sponsors of the entreprise architecture initiative ;-)

And finally, Entreprise Architects have much, much more accurate skills -of course- than the lame "IT designers" (solution architects? tech leads?). Hopefully for the Entreprise Architects' ratings, TOGAF doesn't retain "humility" as a criteria... ;-)

By the way, this lack of humility pitfall reminds me a former & excellent tweet from Martin Thompson (probably one of the finest technical architect you can find), saying:

How to be an architect:
1. Stop programming
2. Stop learning
3. Convince yourself nothing has changed since you did #1 and #2.

And finally, even if it's highly recommended to blend TOGAF and ADM to your context and organization, the huge number of outputs, tools and steps per phase (10 phases at max, with 8-15 steps per phases) can clearly lead us to a dogmatic and bureaucratic hell if the people in charge of setting up the architecture capability within our entreprises are not mature, or pragmatic enough.


More than TOGAF, the practice of entreprise architecture seems key to ensure that large scale organizations are able to align themselves to their strategy and to face the challenges related to the management of their capabilities.

TOGAF has some good ideas, but is intrinsically not adapted to agility best practices (nor continuous delivery for instance). Thus, we will need to find how to bend TOGAF strong enough to be continuous delivery compliant, or -more likely- to find something else than TOGAF for our modern entreprise architecture practice. 

But whatever the methodology and since the ivory tower syndrome is threaten every architect, it seems crucial to me to setup some risk mitigation/protection mechanisms within those organizations, in order to avoid situations where architect without continuous improvement mindset (and not aware that they need to seek assistance from other people's expertises) to be those who hold the keys to achieve the entreprise's objectives. 

When a developer stops learning things and improving himself as a professional, bad things happen. But when an architect is falling into the same laziness, VERY bad things happen ;-(

Wanna start the brainstorming to find solutions to those questions?