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Chimera

16 papers tagged archive 2025-07-28

Introduced by Shigang Li et al. in Chimera: Efficiently Training Large-Scale Neural Networks with Bidirectional Pipelines

archive 2025-07-28 Description, source and code snippet are the archive's method entry.

Chimera is a pipeline model parallelism scheme which combines bidirectional pipelines for efficiently training large-scale models. The key idea of Chimera is to combine two pipelines in different directions (down and up pipelines).

Denote N as the number of micro-batches executed by each worker within a training iteration, and D the number of pipeline stages (depth), and P the number of workers.

The Figure shows an example with four pipeline stages (i.e. D=4). Here we assume there are D micro-batches executed by each worker within a training iteration, namely N=D, which is the minimum to keep all the stages active.

In the down pipeline, stage₀∼stage₃ are mapped to P₀∼P₃ linearly, while in the up pipeline the stages are mapped in a completely opposite order. The N (assuming an even number) micro-batches are equally partitioned among the two pipelines. Each pipeline schedules N/2 micro-batches using 1F1B strategy, as shown in the left part of the Figure. Then, by merging these two pipelines together, we obtain the pipeline schedule of Chimera. Given an even number of stages D (which can be easily satisfied in practice), it is guaranteed that there is no conflict (i.e., there is at most one micro-batch occupies the same time slot on each worker) during merging.

PaperSource

Papers archive 2025-07-28

16 shown of 16, newest first. Repository counts are the archive's code-links table. A Syntology line states what Syntology ran from that paper's harvested code; it is per sample and not a correctness claim.

Tasks archive 2025-07-28

20 shown of 29 tasks the archive attaches to papers tagged with this method, by distinct papers. A task without a page in the catalog is plain text.

TaskPapers
State Space Models2
Active Learning1
All1
Anomaly Detection1
Descriptive1
Drug Discovery1
GPU1
High-Level Synthesis1
Human Detection1
Hybrid Machine Learning1
Language Modeling1
Language Modelling1
Mamba1
Math1
Neural Architecture Search1
Object Detection1
Position1
Property Prediction1
Retrosynthesis1
Scheduling1

Usage over time archive 2025-07-28

Papers per year tagged with Chimera: 2021 to 2025, peak 7 7 0 2021: 1 paper 2021 2022: 4 papers 2022 2023: 2 papers 2023 2024: 7 papers 2024 2025: 2 papers 2025
Papers per year the archive tags with this method, by the paper's archive date (16 dated). Bars are counts, not a trend claim.

Components: the archive holds no method-to-method composition, so PwC's Components table cannot be rebuilt; the Papers list carries no Results column for the same reason (the archive does not join its leaderboard rows to method tags).

Categories archive 2025-07-28

Distributed MethodsSynchronous Pipeline ParallelModel Parallel Methods

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