What is the difference between Hard and Soft real-time systems ?
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Answer / prajesh
In Real time system correctness of an operation depends not
only on the logical correctness but it should be
deterministic. Real time system are of two types, hard and
real. In hard real time system any output after the
deadline should be treated as useless,so it lead to
complete failure. But in soft realtime some late answer
also consider as a right answer, it tolerate such lateness
| Is This Answer Correct ? | 163 Yes | 27 No |
Answer / water
A hard real-time system guarantees that critical tasks
complete on time. This goal requires that all delays in the
system be bounded from the retrieval of the stored data to
the time that it takes the operating system to finish any
request made of it. A soft real time system where a critical
real-time task gets priority over other tasks and retains
that priority until it completes. As in hard real time
systems kernel delays need to be bounded
| Is This Answer Correct ? | 60 Yes | 12 No |
Answer / kwrtos
Often a hard real-time system operates on a preemptive,
context switching operating system where tasks will be
switched in and out execution state upon its defined and
scheduled time slots to maintain its real-time
characteristics. A soft real-time system, often denotes a
system that attempts to meet all time constaints imposed by
its tasks or operations or applications by enjoying the
powerful system resources such as high clock rate, faster
processors, speedy cache, and lightening buses. Yet, it is
still a 'soft' real-time system because some critical tasks
might be delayed due to some system-oriented processes that
are bulky and time-consuming and not preemptive.
| Is This Answer Correct ? | 63 Yes | 38 No |
Answer / nishad
A hard real time system is the one in which all the tasks
have to be completed within a specified deadline. Where as
there is no any such deadlines present in soft real time
systems.
| Is This Answer Correct ? | 31 Yes | 9 No |
Answer / prabhash awasthi
In hard real time system the late output is harmful and can
not be tolarate,while in soft real time sytem the late
output is annoying and but can be tolarate.
most general purpose OS are made in soft real time system.
| Is This Answer Correct ? | 18 Yes | 5 No |
Answer / omari jk
*Hard real-time system
1. Secondary storage limited or absent, data stored in short- term memory, or read-only memory (ROM)
2. Conflicts with time-sharing systems, not supported by general-purpose operating systems.
*Soft real-time system
1. Limited utility in industrial control or robotics
2. Useful in applications (multimedia, virtual reality) requiring advanced operating system features.
| Is This Answer Correct ? | 17 Yes | 5 No |
Answer / yashpal
Hard real-time systems must have at least some actions with hard deadlines. But the converse is not true - soft real-time systems may have actions with hard deadlines. Those systems are soft real-time because they do not employ the hard real-time sequencing timeliness criterion, they employ soft real-time ones such as "minimize the expected number of missed deadlines," regardless of whether the deadlines are hard or soft.
| Is This Answer Correct ? | 5 Yes | 3 No |
Answer / diksha
In a hard real time system ,the peak load performance much be predictable and should not violate the predefined deadlines. In a soft real time system, a degraded operation in a rarely occurring peak load can be tolerated.
| Is This Answer Correct ? | 1 Yes | 2 No |
Answer / surendra singh
hard real-time" and "soft real-time" apply only to a "system," because their definitions are based on sequencing. In this sense, a system is any resource management facility that includes sequencing (of threads, only by our convention in this document), anywhere from the hardware up through the OS and middleware to the application(s)
| Is This Answer Correct ? | 4 Yes | 6 No |
Answer / rajan
soft real time system:it is used in critical application
like robotics,industrial control etc.
real time sys:the few application which it use in plantary
rover'smultimedia, undersea exploration.
| Is This Answer Correct ? | 14 Yes | 25 No |
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