WorksheetsDDIA, chapter 8, The Trouble With Distributed Systems
Total questions: 9
Worksheet time: 9mins
What fits better to word Deterministic?
some parts of the system that are broken in some unpredictable way
well defined (algorithm)
the same operation always produces the same result
monotonic(clock)
A network problem can occur:
while using a public cloud service
in controlled environments like a datacenter operated by one company
between two service connected through Internet
How long should be the timeout to surely detect a faulting node?
short timeout to detect problem faster
long timeout to lower a risk of incorrectly declaring a node dead
there is no simple answer
What kind of network uses bounded delay?
cellular
VoIP
traditional fixed-line telephone network
Which type of clock is more reliable for LWW (last write wins) strategy?
logical clock
monotonic clock
time-of-day clock
Select features of RTOS (Real time operating system):
High performance
very expensive
guaranteed allocation of CPU time in specified intervals
dynamic memory allocation may be restricted or disallowed entirely
What is fencing token?
a lock granted by server
a number that increases every time a lock is granted by server
a check on a client side to ensure that lease is not expired
timestamp range used to calculate the order of operations
bounded network delay, bounded process pauses, and bounded clock error are attributes of:
Synchronous model
Partially synchronous model
Asynchronous model
if we are generating fencing tokens for a lock, we may require the algorithm to have the following properties:
availability
eventual consistency
monotonic sequence
uniqueness
