Amdahl's law

E219378

Amdahl's law is a formula in computer architecture and parallel computing that predicts the maximum performance improvement achievable by parallelizing parts of a system, given that some portion must remain serial.

All labels observed (3)

Label Occurrences
Amdahl's law canonical 8
Amdahl's argument 1
Amdahl’s law 1

How this entity was disambiguated

Statements (48)

Predicate Object
instanceOf computing law ⓘ
formula ⓘ
performance law ⓘ
theorem in parallel computing ⓘ
alsoKnownAs Amdahl's argument ⓘ
linked to: Amdahl's law
appliesTo GPU acceleration ⓘ
I/O-bound and CPU-bound workload decomposition ⓘ
distributed systems ⓘ
multi-core processors ⓘ
assumes fixed total problem size ⓘ
no overhead for communication and synchronization in its basic form ⓘ
remaining portion of the workload is perfectly parallelizable ⓘ
some portion of the workload is strictly serial ⓘ
contrastedWith Gustafson's law ⓘ
coreConcept diminishing returns from adding more processors ⓘ
serial bottleneck limits overall speedup ⓘ
speedup is bounded by non-parallelizable fraction ⓘ
defines N as number of processors or parallel units ⓘ
P as fraction of workload that is parallelizable ⓘ
S as overall speedup ⓘ
describes effect of serial fraction on parallel speedup ⓘ
limit of performance improvement from parallelization ⓘ
maximum speedup of a system using multiple processors ⓘ
field computer architecture ⓘ
high-performance computing ⓘ
parallel computing ⓘ
performance analysis ⓘ
formalExpression S = 1 / ((1 − P) + P / N) ⓘ
historicalContext formulated in the 1960s ⓘ
introduced in the context of mainframe and multiprocessor design ⓘ
implies even small serial fractions severely limit speedup ⓘ
improving serial portion can be more beneficial than adding processors ⓘ
maximum speedup as N approaches infinity is 1 / (1 − P) ⓘ
influenced design of parallel architectures ⓘ
thinking about limits of parallel processing ⓘ
limitation assumes constant serial and parallel fractions independent of N ⓘ
does not account for changing problem size ⓘ
ignores communication and synchronization overheads in simple form ⓘ
namedAfter Gene Amdahl ⓘ
relatedTo bottleneck analysis ⓘ
law of diminishing returns ⓘ
parallel speedup ⓘ
strong scaling ⓘ
usedFor analyzing trade-offs in system optimization ⓘ
estimating scalability of parallel programs ⓘ
evaluating benefits of hardware acceleration ⓘ
guiding design of multiprocessor systems ⓘ
performance modeling ⓘ

How these facts were elicited

Referenced by (10)

Full triples — surface form annotated when it differs from this entity's canonical label.

Gene Amdahl → knownFor → Amdahl's law ⓘ
Gene Amdahl → notableConcept → Amdahl's law ⓘ
Wirth’s law → relatedTo → Amdahl’s law ⓘ
linked to: Amdahl's law
Gene Amdahl → knownFor → Amdahl's law ⓘ
subject linked to: Amdahl
Gene Amdahl → formulated → Amdahl's law ⓘ
subject linked to: Amdahl
Amdahl's law → alsoKnownAs → Amdahl's argument ⓘ
linked to: Amdahl's law
Gene Amdahl → knownFor → Amdahl's law ⓘ
subject linked to: Andor International
The Free Lunch Is Over → mentions → Amdahl's law ⓘ
Gustafson's law → contrastsWith → Amdahl's law ⓘ
Gustafson's law → relatedTo → Amdahl's law ⓘ