Which of the following characteristics would allow a bacterium to adhere to a human intestinal lining?

Dre’s car engine runs at . On a day when the outside temperature is , he turns off the ignition and notes that 1 minute later, the engine has cooled to . What formula – y(t), will represent the temperature of the engine at time ?

Type the scientific name of humans.

All bacteria that currently exist are: 

Chemoautotrophs use ______.

Potpourri_3b Potpourri The context for this question is the same as the previous question: 3.  Recall that locks require respective atomic operations (e.g., naive spin lock uses test_&_set; ticket lock and array-based lock use fetch_&_inc; linked-list lock uses fetch&store and compare_&_swap).  In a multiprocessor system with hardware cache coherence, multiple cores keep cached copies of data consistent by invalidating or updating caches on writes. This design makes certain locks “noisier” than others—i.e., they produce more cache coherence (invalidation) traffic under contention.  b. True or False with justification. A ticket lock is often noisier than a queue-based lock (either an array-based lock or a linked-list lock) under heavy contention.

Potpourri_2a Potpourri 2. Answer the following questions with reference to Xen’s I/O ring data structure. The I/O ring is a circular buffer used by Guest Operating systems for enqueuing requests for the Hypervisor, and collecting its responses. a. You wish to improve I/O ring design by providing APIs in the guest OS to throttle the request creation. Assume the Guest OS needs just the number of outstanding requests to decide if it should throttle the requests. Is it possible to get this number of outstanding requests in the current implementation? Why or why not?

Potpourri_1 Potpourri 1. In designing the L3 microkernel, Liedtke further strengthens the conclusions of SPIN/Exokernel. Justify your answer.

Virtualization_3 Memory Management   3. In VM oblivious page sharing, what are the main performance overheads compared to using dedicated machine memory pages for each VM?

Parallel_Systems_1a Shared Memory Machines 1. a. You are trying to explain the principles of sequential consistency and cache coherence to your friend. Your friend claims that cache coherence implies sequential consistency. Do you agree with your friend’s claim? If not, state how you will convince your friend that they are not the same.