RESEARCH INITIATIVES/Information Retrieval & Systems
DPLA-Retriever: Memory-Efficient Web-Scale Retrieval and Single-GPU LLM Co-location
Information Retrieval & Systems● ACTIVE RESEARCH

DPLA-Retriever: Memory-Efficient Web-Scale Retrieval and Single-GPU LLM Co-location

Project Summary

A memory-efficient multi-tier retrieval framework indexing 21 million Wikipedia passages inside 2.58 GB active VRAM, allowing full co-location of an 8B LLM reader on a single consumer GPU.

RESEARCH OVERVIEW & DETAILS

Project Scope & Details

DPLA-Retriever (Decoupled Parameter-disjoint Latent Attention) resolves the multi-vector memory bottleneck in web-scale retrieval. By dynamically synthesizing 8 compact latent memory tokens via Perceiver Cross-Attention on-the-fly and employing Entity-Gated 2-Hop Adaptive Bridging, DPLA searches the complete 21,015,324-passage English Wikipedia corpus on a single NVIDIA GeForce RTX 4090 within 2.58 GB active VRAM (8.7x lower than ColBERT v2). This leaves 21.4 GB free to co-locate an 8B LLM reader (Llama-3-8B) on the same GPU, delivering 37.90% MuSiQue R@20 at 3.80 ms amortized query latency (263.2 QPS).

ARCHITECTURAL & SCIENTIFIC HIGHLIGHTS
01.

Decoupled Parameter Latent Attention

Decoupled dual-phase architecture executing full-corpus 21M passage search within 2.58 GB active VRAM.

02.

Single-GPU 8B LLM Co-location

Frees over 21.4 GB of VRAM on a single NVIDIA RTX 4090 to host an 8B parameter reader model (Llama-3/Mistral).

03.

Entity-Gated 2-Hop Adaptive Bridging

Dynamic routing router automatically triggers secondary hops on multi-hop questions while bypassing single-hop queries.

04.

Sub-4ms Amortized Retrieval

High-throughput vector search delivering 263.2 queries per second across English Wikipedia.

PROJECT GALLERY [2 PHOTOS]
Click to expand
DPLA Multi-Tier Architecture
FIG. 01

DPLA Multi-Tier Architecture

Memory Footprint & Hardware Economics
FIG. 02

Memory Footprint & Hardware Economics

ACADEMIC PUBLICATIONS [1]
2026Under Review / ACM Web Conference (WWW 2026)

Memory-Efficient Multi-Tier Retrieval for Web-Scale Passage Search and Single-GPU LLM Co-location

Authors: Chaitanya Anand, Himangshu Sarma

RESEARCH TEAM
  • Chaitanya Anand
  • Dr. Himangshu Sarma
EXTERNAL COLLABORATORS
  • ACM WWW 2026
TECHNOLOGIES
Information RetrievalMulti-Vector MaxSimPerceiver Cross-AttentionFAISS IVF-PQLLM Co-locationPyTorchLoRA Disjoint Adapters
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