Questão 1
Questão
In the Microkernel architecture of VMs:
Responda
-
Drivers are part of the Guest VMs
-
Drivers are part of the Hypervisor
-
Drivers are part of a specific service VM
-
Drivers are part of the Guest OS
Questão 2
Questão
Which statement about Paravirtualization is correct?
Responda
-
It is the same of Kernel-level Virtualization
-
Guest OS and VMM are independent each other
-
It cannot be used with traditional Operating Systems
-
Hooks are not required
Questão 3
Questão
Which is the goal of the "machine-learning software as a service"?
Responda
-
Provide networking paradigms for machine learning
-
Provide ready-to-use machine learning applications
-
Provide platform and toolboxes for machine learning
-
Provide hardware infrastructures for machine learning
Questão 4
Responda
-
emulates only the ISA but not the ABI
-
emulates only the ABI and not the ISA
-
reproduces the machine by providing not only ABI but ISA (user/ system)
-
supports the Java Runtime Environment
Questão 5
Questão
Does an emulator read, interpret and execute all the bytes included in the memory of system it is going to reproduce?
Questão 6
Questão
The program in warehouse-scale computing may consist of tens or more individual programs:
Questão 7
Questão
Data centers are buildings where multiple servers and communication units are co-located
Questão 8
Questão
What is a computing infrastructure?
Questão 9
Questão
Tower servers consumes less space than rack and blade:
Questão 10
Questão
Blade servers require expensive configurations:
Questão 11
Questão
TOR switch refers to:
Responda
-
Tower switch
-
Top-of-rack switch
Questão 12
Questão
Racks shelves may contain switches:
Questão 13
Questão
What is a Network Attached Storage (NAS)?
Responda
-
a storage system directly attached to a server or workstation
-
a computer connected to a network that provides only file-based data storage services to other devices
-
a remote storage unit connected to PC using a specific networking technology
-
a computer connected to a network that provides computation to other devices
Questão 14
Questão
Downtime is a period of time, or a percentage of a time span, when a system is unavailable or offline __________
Questão 15
Questão
In a three-layer network architecture of a Datacenter, which is the layer that is typically associated to the TOR switch?
Responda
-
Access
-
Core
-
Aggregation
-
None of the others
Questão 16
Questão
Which definition is not encompassed by Dependability:
Responda
-
Reversibility: ability to reverse a broken service
-
Reliability: continuity of correct service
-
Maintainability: reparation to restore correct service
-
Availability: readiness for correct service
Questão 17
Questão
In the context of SSDs, Blocks are the smallest unit that can be read/written
Questão 18
Questão
Paravirtualization is a particular type of kernel-level Virtualization that does not rely on a host OS
Questão 19
Questão
The structure (or topology) of a reliability block diagram is always the same as the structure (or topology) of the modeled system
Questão 20
Questão
A system virtual machine provides a complete system environment that can support an operating system (potentially with many user processes)
Questão 21
Questão
Which sentence about Tier Level 4 of datacenter is not correct?
Responda
-
Fault-tolerant site infrastructure with availability of 99.995%
-
Meets or exceeds all Tier 3 requirements
-
Single non-redundant distribution path serving the IT equipment
-
All cooling equipment is independently dual-powered
Questão 22
Questão
What is a hybrid cloud computing system?
Responda
-
a cloud used for a single organization
-
a cloud whose energy is produced both by diesel and batteries
-
a cloud shared by several organization
-
a cloud composed by private and public cloud systems
Questão 23
Questão
Paravirtualization cannot be used with unmodified OS
Questão 24
Questão
Servers in data centers are like regular personal-computers with the same form factor
Questão 25
Questão
Warehouse-scale computers run a large number of very small applications
Questão 26
Questão
An Edge Computing system provides higher performance (in terms of memory and computation) than Internet-of-Things devices:
Questão 27
Questão
Which of the following is not a feature of a fat tree topology in a data center network architecture?
Responda
-
None of the others
-
It has multiple connections to the core
-
It has a recursive organization
-
It has a three-tier model
Questão 28
Questão
In the context of SSDs, one of the following activities is NOT managed by the Flash Translation Layer:
Responda
-
Defragmentation
-
Address Translation
-
Garbage Collection
-
Data Allocation
Questão 29
Responda
-
Provides the interface to system ISA and user ISA
-
Provides the interface to system ABI and the user ISA
-
Provides the interface to system ABI and the user ABI
-
Provides the interface to system calls and user ABI
Questão 30
Questão
Consider an array of N disks. Select the right order of the RAID levels in terms of effective data storage in ascending order, i.e. for the lower to the higher data storage availability.
Responda
-
RAID 1+0, RAID 6, RAID 5
-
RAID 6, RAID 5, RAID 1+0
-
None of the others
-
RAID 1+0, RAID 5, RAID 6
Questão 31
Questão
Warehouse-scale computers belong to a single organization, use a relatively homogeneous hardware and system software platform, and share a common systems management layer
Questão 32
Questão
All faults occurring in a system cause a failure of the system
Questão 33
Questão
In the context of SSDs, Pages are the smallest unit that can be erased
Questão 34
Questão
Graphical Processing Units support data-parallel computation
Questão 35
Questão
A deep neural-network cannot be trained on multiple Graphical Processing Units
Questão 36
Questão
A System Virtual Machine can provide its functionality:
Questão 37
Questão
Hybrid Clouds are systems where one or more public cloud services are combined with private data
center resources into a single virtually managed environment.
Questão 38
Questão
Graphical Processing Units within a tray are connected using high-bandwidth interconnects, such as NVlink:
Questão 39
Questão
The need for a constant Internet connection is one of the advantages of data centers
Questão 40
Questão
In-rack cooling refers to cooling equipment where the cooling coils are adjacent to the rack.
Questão 41
Questão
Warehouse-scale computers belong to a single organization, use a relatively homogeneous hardware and system software platform, and share a common systems management layer
Questão 42
Questão
In datacenter storage context, DAS means Distributed Application Storage:
Questão 43
Questão
Which is the difference between Guest and Host?
Responda
-
Guest: the underlying platform supporting the environment/system; Host: the software that runs in the VM environment
-
Guest: the software that runs in the VM environment; Host: the underlying platform supporting the environment/system
-
Guest: the underlying platform supporting the environment/system; Host: the virtual machine manager supporting the execution of virtual machines
-
Guest: the underlying platform running in the virtual machine manager; Host: the software that runs in the VM environment
Questão 44
Questão
To increase reliability, which of the following actions is not correct?
Responda
-
Use multiple redundant components
-
Reduce MTTR to a minimum
-
Have spare components at disposal
-
Use elements with higher MTTF
Questão 45
Questão
Warehouse-scale computers can be designed to operate on multiple data centers
Questão 46
Questão
Rotational delay is the time to rotate the read head to reach the desired track
Questão 47
Questão
A system having very small reliability may have large availability
Questão 48
Questão
In the context of data centers, scalability is the ability for the infrastructure __________ without cost, efficiency, and reliability being compromised. Select the correct item to be included in the previous sentence.
Responda
-
to be enlarged or to handle an increment of the input requests
-
to run in a larger building
-
none of the others
-
to improve the cooling strategy
Questão 49
Questão
Which is the most appropriate definition for "fault"?
Responda
-
Any library inconsistency in the Operating System
-
Any defect in the silicon caused by dust particles during manufacturing
-
Any inappropriate usage of the system
-
Any event interfering with the nominal behavior of the system
Questão 50
Questão
One of these levels is NOT part of a typical three-layers network architecture of a data-center?
Responda
-
Access
-
Aggregation
-
Core
-
Cloud
Questão 51
Questão
In the context of rack servers, 1U is 44.45cm
Questão 52
Questão
In a reliability block diagram, adding components in series decrease the system reliability with respect to the reliability of the single component
Questão 53
Questão
Warehouse-scale computers run a large number of very small applications
Questão 54
Questão
What are the benefits of data center virtualization?
Responda
-
All of the other answers listed are correct.
-
Consolidation and ease of manageability.
-
Cost savings in power and cooling of the data center.
-
Flexibility and agility.
Questão 55
Questão
When dependability-related requirements must be considered?
Responda
-
Only during requirements definition
-
When starting testing/verification activities
-
When a prototype of the system is available
-
In every phase of the design flow
Questão 56
Questão
The program in warehouse-scale computing is a service provided by internet:
Questão 57
Questão
Traditional data centers can host hardware and software for multiple organizational units or different companies.
Questão 58
Questão
Which is the configuration characterizing the three-layers network architecture of a data-center?
Responda
-
Sensors – Aggregation – Cloud
-
Access - Aggregation – Cloud
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Access – Aggregation – Core
-
Access – Fog – Core
Questão 59
Questão
Tower servers have a cable management that is more complex than Rack ones:
Questão 60
Questão
Gmail is an example of:
Questão 61
Questão
Consider an array of N disks. Select the right order of the RAID levels in terms of effective data
storage in descending order, i.e. for the higher to the lower data storage availability.
Responda
-
RAID 0, RAID 4, RAID 6
-
RAID 6, RAID 0, RAID 4
-
None of the others
-
RAID 4, RAID 6, RAID 0
Questão 62
Questão
Data centers are well suited for real-time decisions in autonomous car context
Questão 63
Questão
After a fault activation the system is always expected to fail
Questão 64
Questão
The reliability of a Triple Modular Redundancy (TMR) system is always greater than the reliability
of the single copy of the system
Questão 65
Questão
What is a Data Center?
Responda
-
None of the others
-
A building or portion of a building whose primary function is to research new data.
-
A building or a portion of a building whose primary function is to house a computer room and its related support areas.
-
A room in a building dedicated to monitoring data and information.
Questão 66
Questão
Seek delay is the time needed by the disk to place the desired sector under the read head
Questão 67
Questão
What is the Hardware-level virtualization?
Responda
-
The virtualization layer is placed between the operating system and the applications
-
The virtualization layer is above the applications
-
The virtualization layer is placed between the hardware and the operating system
-
The virtualization layer is placed below the hardware
Questão 68
Questão
Which aspect is a drawback of data center computing platform?
Questão 69
Questão
Racks shelves are used to store servers and other IT equipments:
Questão 70
Questão
In warehouse-scale computers the software running on these systems executes on clusters of hundreds to thousands of individual servers
Questão 71
Questão
In a data center for AI, servers includes both general purpose CPUs and accelerators (such as
GPUs, TPUs and FPGAs):
Questão 72
Questão
NVlink is a low-bandwidth connection among Graphical Processing Units:
Questão 73
Responda
-
Provides the interface to system calls and user ABI
-
Provides the interface to system ABI and the user ISA
-
Provides the interface to system calls and user ISA
-
Provides the interface to system ABI and the user ABI
Questão 74
Questão
One of these configurations is not considered in Data-center network architectures. Which one?
Responda
-
D-Cell
-
Three layers
-
Fat-tree
-
Direct Connections
Questão 75
Questão
What is the average latency for an Hard Disk Drive?
Responda
-
Time to wait for the sector
-
Time to wait for the data transfer
-
Time to wait for the head movement
-
Time to wait for the cylinder
Questão 76
Questão
In the context of SSDs, Pages are the smallest unit that can be read/written
Questão 77
Questão
In-row cooling adds an air-to-water heat exchanger at the back of a rack so the hot air exiting the
servers immediately flows over coils cooled by water.
Questão 78
Questão
Select the wrong definition. A Virtual Machine:
Responda
-
none of the others
-
may appear as having different resources than the physical machine
-
may result in a different level of performance with respect to the physical machine
-
provides identical software behavior
Questão 79
Questão
Tower servers can be cooled easily:
Questão 80
Questão
What is the TBW in a Solid State Disk?
Responda
-
Total amount of data that must be written into an SSD before the completion of the space
-
Total amount of data that can be written into an SSD before it is likely to fail
-
Total amount of data that can be read from an SSD
-
Total amount of data that can be written into an SSD
Questão 81
Questão
The following sentence: "The probability that the component does not fail in the interval 0 ... t,
knowing that at the instant t = 0 the component was working correctly" defines:
Responda
-
Dependability
-
Reliability
-
Availability
-
None of the other
Questão 82
Questão
Consider an array of N disks. Select the right order of the RAID levels in terms of MTTFRAID
in descending order, i.e. for the higher to the lower MTTF. Consider a number of disks N that is
large enough to satisfy the minimum requirements for all the RAID levels.
Responda
-
None of the others
-
RAID 5, RAID 1+0, RAID 0+1
-
RAID 1+0, RAID 0+1, RAID 5
-
RAID 0+1, RAID 5, RAID 1+0
Questão 83
Questão
Racks servers have a cable management that is more complex than Tower ones:
Questão 84
Questão
Traditional data centers typically host a large number of relatively small- or medium-sized applications
Questão 85
Questão
In-row cooling works like in-rack cooling except the cooling coils are not in the rack, but adjacent
to the rack.
Questão 86
Questão
Rack, blade and towers are form factor of servers in data centers
Questão 87
Questão
Warehouse-scale computers comprise important components related to power delivery, cooling, and building infrastructure
Questão 88
Questão
What is a Graphical Processing Unit (GPU)?
Responda
-
A specialized hardware meant to provide storage in a data center
-
A specialized hardware meant to support data-parallel computation
-
An Internet-of-Things device meant to operate in the field
-
A specialized hardware meant to provide networking in a data center
Questão 89
Questão
Rack servers need additional cooling systems due to their high overall component density
Questão 90
Questão
Is the Java Runtime Environment an example of system virtual machine?
Questão 91
Questão
Which is the main characteristic of the D-Cell topology for data center network architectures?
Responda
-
The network is organized in a distributed way
-
The network comprises edge, aggregation and core layers
-
the network is organized in a recursive way
-
the network is organized in a hierarchical way