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Measured

Research

01

Reclaim Hysteresis in Multi-Tenant Memory Reclamation

Independent systems research · Experimentation phase

2026 · In progress

Paper · DOCX

The claim is not merely that reclaim hurts. It is that an equal reclaim can hurt differently because earlier reclaim changed which pages remain.

This work asks whether memory reclamation has memory of its own. When a kernel preferentially evicts cold pages, the remaining resident set becomes hotter; an equal reclaim action can therefore impose a different future cost until evicted pages refault. The current theory models that recovery from the victim-conditioned access-rate distribution and represents each tenant’s accumulated history as reclaim debt.

The research is now moving from theory to measurement. The next tests estimate page-access-rate distributions, preregister recovery-curve predictions, and compare randomized reclaim against a uniform-access negative control. The access-rate estimator, cold-frontier controller, history-aware water-filling policy, and randomized assay are not yet implemented; existing measurements characterize the experimental substrate only.

Linux memory managementcgroup v2page reclaimonline controlexperimental systems

Status

PhaseExperimental design
Next testRandomized reclaim

Mechanism

Cold-page eviction changes the resident-set composition; refaults gradually erase that history.

Falsification

The effect should disappear under homogeneous access rates and be abandoned if preregistered recovery predictions fail.

  1. 01

    Mechanism

    defined

    Cold-page eviction changes the access-rate distribution of the surviving resident set.

  2. 02

    Access-rate estimator

    not built

    Estimate the distribution needed to predict how reclaim cost should recover over time.

  3. 03

    Randomized reclaim

    next test

    Intervene on reclaim volume, then measure the recovery curve against a preregistered prediction.

  4. 04

    Uniform-access control

    planned

    The proposed history effect should disappear when pages have homogeneous access rates.

  5. 05

    Controller policy

    evidence-gated

    A history-aware allocation policy is only justified if the mechanism survives both tests.

advance

Recovery follows the preregistered curve and differs from the negative control.

stop

The prediction fails or the homogeneous control shows the same effect.

Current truth: the theory and experiment design exist; the estimator, reclaim assay, and controller policy do not. This page will change when the evidence does.
02

Hardware-Efficient Compiler Optimization

NC State University · Undergraduate Research Assistant

Aug – Nov 2024

This work focused on generating hardware-efficient code for datacenter workloads. I built compiler passes for SIMD vectorization, loop tiling, and cache-aware scheduling, then extended an LLVM/MLIR pipeline with fusion, common subexpression elimination, and strength reduction to reduce memory traffic.

The same pipeline used hardware-aware cost models for cache and NUMA effects, instruction throughput, and memory bandwidth to guide auto-tuning across CPU and GPU kernels. On representative benchmarks, the combined work improved end-to-end latency by 32.478% and throughput by 15.821%.

C++LLVMMLIRFPGAcompiler optimization

Results

End-to-end latency−32.478%
Throughput+15.821%

Transforms

SIMD vectorization, loop tiling, fusion, common subexpression elimination, and strength reduction

Cost model

Cache and NUMA behavior, instruction throughput, and memory bandwidth