Page 110 - How Cloud Computing Is Transforming Business and Why You Cant Afford to Be Left Behind

MANA GEMENT STRATEGIES F O R THE CL OUD R EV OL UTION

system. Even though DEC disappeared inside Compaq Com-
puter years ago (and Compaq, in turn, inside HP), these old
products grind on. There are still some of all these machines
around—and their legacy applications won’t coordinate very
well with the cloud. Even new software, bought as packages
from Oracle, SAP, or Microsoft, tends to get customized by

its new owner and set up with special dependencies on other
systems. As the complexity grows, so does the work of the com-
puting professionals who tend these systems and keep every-
thing on track.
Most of all, they have to guard against occasional peaks in
workload that may prove to be too much for any one system,
resulting in a crash. If a key data center system fails, then other

systems that depend on it will stall, as their calls for comput-
ing results will go unanswered. Because the professionals man-
aging this complexity are responsible for keeping everything
running, they’ve learned to overallocate resources rather than
trying to cut the margin too thin. For many years, a single x86
server would run one application to avoid the possibility of
hidden conflicts between two different applications on the
same server. Such a practice was wasteful of hardware; it often
used only 15 percent of the server’s capabilities, and this fig-

ure sometimes dropped into the 5 to 7 percent range, but the
solution was cheap compared to the pain of user protests over
outages and the expense to fix them. Likewise, disk drives al-
located to an application for storing its data were also over-
supplied; a typical rate of disk drive usage to this day is only
30 percent—excess capital expense that might be avoided
through a different method of managing these resources.

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