"So let's look at two of the most common operating systems used
today used in datacenters and on server systems. On one hand,
Windows and the other Linux.
"Windows by nature has more downtime per system, because
Microsoft releases patches that require frequent rebooting. Windows
patches are scheduled to be released on the second Tuesday of each
month, so at a minimum once per month Windows systems will need to
reboot. Sometimes, patches are released even more frequently,
depending on the severity. Windows just can't activate a majority
of software updates without rebooting the entire system.
"And now let's take a look at Linux. By nature, Linux is
designed to run indefinitely unless the running kernel itself needs
to be upgraded. However there have been breakthroughs within the
past year (Ksplice is one) where even the kernel itself can be
upgraded without a reboot."