docs/tugas kuliah/os-kernel-allocatorTugas Kuliah

Virtual Memory & Slab Allocator

Kernel-space buddy memory allocator and slab cache manager designed for low-overhead page frames and object reuse.

main•GPL-3.0•Operating Systems & Low-Level Architecture (Semester 4)•36•28•620

CAssemblyMakefilePOSIX

GitHub

Files (1)README Documentation

Source Code & File Hierarchy

Branch: main

os-kernel-allocator/src

1 item

.. (direktori induk)

allocator.c

1.6 KB

Repository Overview & Architecture

README.md•1 min read

Virtual Memory & Slab Allocator

A minimal kernel-space memory management subsystem engineered in C. Combines a binary buddy page allocator for managing physical frame allocations with an object-caching slab allocator for fine-grained kernel structures.

Allocation Hierarchy

code

Physical RAM (Pages of 4096 bytes)
              |
      [Buddy Allocator] (Order 0 to Order 10)
              |
      [Slab Cache Layer] (32B, 64B, 128B, 256B, 512B)
              |
       Kernel Objects (Task structs, Inodes, File descriptors)

Architecture & Design Decisions

Buddy System: Coalesces adjacent power-of-two page frames immediately on deallocation, eliminating external fragmentation while keeping allocation latency bounded.
Slab Cache Recycling: Pre-allocates contiguous memory blocks divided into fixed-size slots, avoiding repetitive zeroing and constructor invocations.
Lockless CPU Free-Lists: Thread-local free lists minimize lock contention in multi-threaded simulation environments.

Verification & Tests

Tested using a synthetic microbenchmark allocating and releasing 500,000 randomized objects up to 4096 bytes. Memory overhead remained within 3.4% of total allocated capacity.

code

# Compile and run test suite
make all
./bin/allocator_test