Please, provide the *full* log. Relevant data may be located elsewhere. Plus, it doesn't even look like a Cool VL Viewer log (display stats are configured to run every minute on it, not every second)... From the very little I can see from the tiny piece of info available in this largely truncated log, there was no out of memory error, neither any bandwidth congestion, but instead a flacky network connection with the sim that finally lead to a disconnection.
Note that griefers
cannot make your viewer consume all the system memory (the Cool VL Viewer also got specific algorithms to prevent out of memory crashes) neither can it flood directly *your* viewer network connection. However, should they send (using a hacked viewer or even a libomv-based fake client) gazillions of bogus message packets to the sim, it could well bring the latter down to its knees, to make it fail to send packets in time to other connected residents (thus the "out of order" packets), and finally to crash or disconnect everyone.
This kind of attack against servers can only be blocked server side, by LL themselves.
I never saw the OS freezing while running the Cool VL Viewer... at worst (and if you disable the "Memory Usage Safety Check" option in the Advanced menu), the viewer would crash after exhausting its own virtual memory address space. What could happen on low RAM systems (< 4Gb RAM) is that the viewer eats up enough memory to cause swapping to start (which then could slow down the OS a lot). In the Cool VL Viewer, simply keep "Memory Usage Safety Check" checked and uncheck "Allow Swapping" to force the viewer to recourse to its memory usage throttling mechanism before the OS would start swapping (but then expect more blurry textures, potential reduction of the draw distance and even resets of your camera to its default position if you were caming far away)