I had the pleasure of reading a Structure 2010 follow up article written by Stephen Lawson titled “VMware’s Maritz: OSes are having their jobs stolen.” In it, Lawson outlines VMWare’s CEO Paul Maritz’ position that modern applications are relying on frameworks farther up on the stack for abstract services that used to be provided by the operating system, and that those frameworks insulate the application from even knowing what the operating system is.
This “commoditization” of the server OS is expected to some degree and is a case of “what’s old is new again.” Looking back through history, we’ve seen software development take on an evolutionary path of abstraction. Starting from assembly (x86 is my personal reference point) through higher order abstractions like C++ through byte code targeting virtual machines (as in the JVM and .NET CLR), we’ve always looked to move away from various OS level complexities in an effort to boost productivity, increase maintainability, and reduce coupling risk. However, these benefits were only considered OK so long as it didn’t jeopardize the programmers’ ability to express complex solutions to complex problems because of functional crippling that might arise from being too abstract. Typically, two things have held true:
- New paradigms in solution expressiveness have driven the introduction of new languages that embody those paradigms. For example, once “modeling” became en vogue, object oriented programming made sense. Now, we’re seeing a resurgence of functional languages or hybrids.
- Transitions in delivery paradigm have typically acted as catalysts to the creation of new frameworks (passive libraries) and runtime technologies (active application layers) to support the new delivery paradigm.
What we’re seeing today in that Cloud is that scale of technology coupled with the introduction of new application architectures and delivery needs that operating systems were not built for. OS’ are general purpose beasts with explicit and valuable capabilities and coordinating a fundamental execution platform. They are not specialized enough to really understand the upstack pressures being exerted on software developers. Clearly, they could be modified to do so, but were never meant to constantly evolve in that fashion. Instead, they are participating as a critical component at the bottom part of a stack.
When we look at SaaS and some of the architecture dimensions specific to SaaS such as multi-tenancy, the need to be able to achieve web-scale, and have operating tools in place to manage the application, we start to see that new modern frameworks, and in many cases, new types of middleware, are needed. This is the whole motivation behind why I helped co-found Apprenda and we set out to create SaaSGrid. In the early days, my co-founders and I frequently had conversations about how today’s applications need not know about OS specifics in order to function properly, which lead to some of the early architecture decisions of having SaaSGrid act as a mechanism that would leverage the decoupling of app components from their underlying network and OS dependencies to help facilitate scale-out (many details, of course, which go beyond the scope of this post.) As SaaSGrid matured, it took on a number of architectural dimensions on a guest application’s behalf, such as providing baseline single instance, multi-tenancy at all tiers or scaling out by offering partitioning services that can help reorganize application component distribution across a network of servers without reconfiguring or rewriting parts of the application. In effect, SaaSGrid started to manifest a number of “OS-like” capabilities, which go far beyond the frameworks that Maritz describes. It seems inevitable that upstack pressures will also hoist value-add solutions away from the core machine/VM OS, but we should all remember that a stack isn’t a stack if the bottom-most piece is missing or instable.The traditional server OS has simply transformed from necessary and sufficient to necessary but not sufficient.
Do you agree that the server OS is becoming commoditized with respect to cloud offerings, or is this an over-dramatization of what’s happening? If you feel the OS is fading into the backdrop, is there an opportunity for the OS to “modernize,” and if so, how?
