Papers › Hierarchical Context Merging: Better Long Context Understanding for Pre-trained LLMs

Hierarchical Context Merging: Better Long Context Understanding for Pre-trained LLMs

16 Apr 2024arXiv:2404.10308archive 2025-07-28

Woomin Song, Seunghyuk Oh, Sangwoo Mo, Jaehyung Kim, Sukmin Yun, Jung-Woo Ha, Jinwoo Shin

Large language models (LLMs) have shown remarkable performance in various natural language processing tasks. However, a primary constraint they face is the context limit, i.e., the maximum number of tokens they can process. Previous works have explored architectural changes and modifications in positional encoding to relax the constraint, but they often require expensive training or do not address the computational demands of self-attention. In this paper, we present Hierarchical cOntext MERging (HOMER), a new training-free scheme designed to overcome the limitations. HOMER uses a divide-and-conquer algorithm, dividing long inputs into manageable chunks. Each chunk is then processed collectively, employing a hierarchical strategy that merges adjacent chunks at progressive transformer layers. A token reduction technique precedes each merging, ensuring memory usage efficiency. We also propose an optimized computational order reducing the memory requirement to logarithmically scale with respect to input length, making it especially favorable for environments with tight memory restrictions. Our experiments demonstrate the proposed method's superior performance and memory efficiency, enabling the broader use of LLMs in contexts requiring extended context. Code is available at https://github.com/alinlab/HOMER.

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4ran · our draft was wrong
1ran · fixture could not drive it
7ran
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repeat_kv alinlab/HOMER/src/homer/modeling_llama.py official repository ran · fixture could not drive it fingerprinted no licence file found · pointer only · 30d7eec482ebf6b1 · report
Chunk alinlab/homer/src/homer/patch_llama.py official repository ran no licence file found · pointer only · 3c5613c7d1dccdba · report
apply_rotary_pos_emb alinlab/HOMER/src/homer/modeling_llama.py official repository ran · our draft was wrong no licence file found · pointer only · bac65c3dafaec040 · report
find_correction_dim alinlab/HOMER/src/homer/embedding.py official repository ran fingerprinted no licence file found · pointer only · 3c92c963bb0cbb73 · report
find_correction_range alinlab/HOMER/src/homer/embedding.py official repository ran no licence file found · pointer only · 763ecb554c17d2fe · report
gather_logits alinlab/homer/src/perplexity.py official repository ran · our draft was wrong no licence file found · pointer only · a38e3baabc117a17 · report
generate_plain alinlab/HOMER/src/passkey.py official repository ran no licence file found · pointer only · fb2e60e07eb16197 · report
get_accumulated_perplexity alinlab/homer/src/perplexity.py official repository ran · our draft was wrong fingerprinted no licence file found · pointer only · fe1fb261101f64ef · report
linear_ramp_mask alinlab/HOMER/src/homer/embedding.py official repository ran no licence file found · pointer only · 5034871c1d2783cf · report
llamadecoderlayer_forward alinlab/HOMER/src/homer/patch_llama.py official repository ran no licence file found · pointer only · 9f58f79f8bcad64f · report
parse_answer alinlab/HOMER/src/passkey.py official repository ran fingerprinted no licence file found · pointer only · 924e90912400c67d · report
rotate_half alinlab/HOMER/src/homer/modeling_llama.py official repository ran · our draft was wrong fingerprinted no licence file found · pointer only · b99eea6376d1e212 · report
_merge alinlab/homer/src/homer/patch_llama.py official repository unverified no licence file found · pointer only · c827204815a2ce17 · report
create_homer_prefix alinlab/HOMER/src/homer/patch_llama.py official repository unverified no licence file found · pointer only · 42dbbee90fbe5feb · report
generate_homer alinlab/HOMER/src/passkey.py official repository unverified no licence file found · pointer only · f102f8067bf8111b · report

Tasks

Long-Context UnderstandingToken Reduction

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