Equation 24 · The Network Is the Computer Again
What does this equation mean?
Read the formula alongside the article passage below. Each part has a deeper page with its role in the equation, the supporting passage and nearby citations.
This equation states an equality: the expressions on both sides have the same value under the article’s assumptions. Read the equation part by part below; each part has a contextual explanation and a link to its mathematical background.
Read it piece by piece
Symbol T_rd
d is part of the quantity the equation computes from the expression on the right.
Symbol n
n is an argument of the function-like quantity on the left; its role is set by that function’s stated inputs.
Symbol p
p is an argument of the function-like quantity on the left; its role is set by that function’s stated inputs.
Symbol β
β is one of the signed contributions combined to compute the quantity on the left.
Symbol gamma
gamma is one of the signed contributions combined to compute the quantity on the left.
=
The expressions on both sides represent the same quantity under the stated assumptions.
See an illustrated explanation →subscript
The lower label selects a particular version, component, or indexed member of the quantity. For example, x₀ and xₜ can be values at different positions.
How to interpret it
Read it with the definitions, units, and assumptions supplied by the article.
What the article says around this equation
But look at the latency term: 2(p-1) grows linearly in the number of participants. A recursive-doubling or tree scheme instead completes in p rounds: . paying a logarithmic latency term but sending the full message in every round, so its bandwidth cost grows with p rather than staying flat.
Sources cited in the article section
- [2] Collective communication: theory, practice, and experience ↗
- [3] NCCL Tests — Performance Reporting and Bus Bandwidth ↗
- [1] Optimization of Collective Communication Operations in MPICH ↗
These citations give research context. Read each source to check which claims it supports.
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