Nirmal Joshua Kapu

Mr. Nirmal Joshua Kapu

Electrical Engineering, Indian Institute of Technology Kanpur, Kanpur, India
orcid

Research Focus & Metrics

Academic Career Length

3Years (2024-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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17 June 2025 in Proceedings of the ACM on Management of Data
Verified
Journal Article
Open access
SAShubham Agarwal
Shubham Agarwal
SSSai Sundaresan
Sai Sundaresan
SMSubrata Mitra
Subrata Mitra
DMDebabrata Mahapatra
Debabrata Mahapatra
AGArchit Gupta
Archit Gupta
SSShiv Saini
Shiv Saini
Retrieval-Augmented Generation (RAG) is often used with Large Language Models (LLMs) to infuse domain knowledge or user-specific information. In RAG, given a user query, a retriever extracts chunks of relevant text from a knowledge base. These chunks are sent to an LLM as part of the input prompt. Typically, any given chunk is repeatedly retrieved across user questions. However, currently, for every question, attention layers in LLMs fully compute the Keys and Values (KVs) repeatedly for the input chunks, as state-of-the-art methods cannot reuse KV-caches when chunks appear at arbitrary locations or with arbitrary contexts. Naive reuse leads to output quality degradation. This leads to potentially redundant computations on expensive GPUs and increases latency. In this work, we propose Cache-Craft , a system for managing and reusing precomputed KVs corresponding to the text chunks (which we call chunk-caches ) in RAG-based systems. We present how to identify chunk-caches that are reusable, how to efficiently perform a small fraction of recomputation to fix the cache and maintain output quality, and how to efficiently store and evict chunk-caches in the hardware for maximizing reuse while masking any overheads. With real production workloads as well as synthetic datasets, we show that Cache-Craft reduces redundant computation by 51% over SOTA prefix-caching and 75% over full recomputation. Additionally, with continuous batching on a real production workload, we get a 1.6× speed up in throughput for both the LLama-3-8B and 70B models and a 2.1× and 2× reduction in end-to-end response latency respectively, compared to prefix-caching, while maintaining generation quality.

18 November 2024 in Preprints.org
Verified
Preprint
Open access
PDF file
Nirmal Joshua KapuNirmal Joshua Kapu
Nirmal Joshua Kapu
RKRaghav Karan
Raghav Karan
This article surveys convolution-based models convolutional neural networks (CNNs), Conformers, ResNets, and CRNNs-as speech signal processing models and provide their statistical backgrounds and speech recognition, speaker identification, emotion recognition, and speech enhancement applications. Through comparative training cost assessment, model size, accuracy and speed assessment, we compare the strengths and weaknesses of each model, identify potential errors and propose avenues for further research, emphasising the central role it plays in advancing applications of speech technologies.

19 November 2024 in TechRxiv
Verified
Preprint
Open access
Nirmal Joshua KapuNirmal Joshua Kapu
Nirmal Joshua Kapu
RKRaghav Karan
Raghav Karan
This article surveys convolution-based models - convolutional neural networks (CNNs), Conformers, ResNets, and CRNNs-as speech signal processing models and provide their statistical backgrounds and speech recognition, speaker identification, emotion recognition, and speech enhancement applications. Through comparative training cost assessment, model size, accuracy and speed assessment, we compare the strengths and weaknesses of each model, identify potential errors and propose avenues for further research, emphasising the central role it plays in advancing applications of speech technologies.

6 January 2025 in Preprints.org
Verified
Preprint
Open access
PDF file
Nirmal Joshua KapuNirmal Joshua Kapu
Nirmal Joshua Kapu
RKRaghav Karan
Raghav Karan
This article surveys convolution-based models convolutional neural networks (CNNs), Conformers, ResNets, and CRNNs-as speech signal processing models and provide their statistical backgrounds and speech recognition, speaker identification, emotion recognition, and speech enhancement applications. Through comparative training cost assessment, model size, accuracy and speed assessment, we compare the strengths and weaknesses of each model, identify potential errors and propose avenues for further research, emphasising the central role it plays in advancing applications of speech technologies.

12 November 2024 in TechRxiv
Verified
Preprint
Open access
Nirmal Joshua KapuNirmal Joshua Kapu
Nirmal Joshua Kapu
MSMihit Sreejith
Mihit Sreejith
Generating executable code from natural language instructions using Large Language Models (LLMs) poses challenges such as semantic ambiguity and understanding task-specific contexts. To address these issues, we propose a system called DemoCraft , which enhances code generation by leveraging in-context learning and demonstration selection, combined with latent concept learning. Latent concept learning introduces additional concept tokens, which are trainable embeddings that capture task-specific knowledge. We then test our system on two major datasets: MBPP and Humaneval . Our experimental results demonstrate that the proposed system achieves an approximate 2x increase in the pass@k metric compared to baseline models. Furthermore, we introduce two novel evaluation metrics: correctness@k and similarity@k . Our empirical studies indicate that our system attains nearly a 3x improvement in these metrics as well.