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Universal Memory Optimizer

Cross-Distribution Linux Memory Optimization Template

Purpose

Bu template, Linux sistemlerde memory optimizasyonu yapar:

  • ZRAM: Compressed RAM-based swap (RAM/2)
  • Disk Swapfile: Emergency fallback (ZRAM/2)
  • Kernel Tuning: Best practices sysctl parametreleri

Architecture

┌─────────────────────────────────────────────────────────────────────────────┐
│                    MEMORY HIERARCHY (Priority Order)                         │
├─────────────────────────────────────────────────────────────────────────────┤
│ Tier 1: Physical RAM                                                         │
│         └── Primary working memory (~100ns latency)                          │
│                       ↓ (memory pressure)                                    │
│ Tier 2: ZRAM = RAM/2 (priority 100)                                          │
│         └── Compressed swap in RAM (~1μs latency)                            │
│         └── zstd compression (~5:1 ratio)                                    │
│         └── Example: 32GB RAM → 16GB ZRAM → ~80GB effective                  │
│                       ↓ (ZRAM exhausted)                                     │
│ Tier 3: Disk Swapfile = ZRAM/2 (priority 10)                                 │
│         └── NVMe/SSD fallback (~150μs latency)                               │
│         └── Example: 16GB ZRAM → 8GB Swapfile                                │
│                       ↓ (all swap exhausted)                                 │
│ Tier 4: Kernel OOM (system default)                                          │
│         └── Trusts kernel's built-in OOM killer                              │
└─────────────────────────────────────────────────────────────────────────────┘

Quick Start

# 1. Standard installation
sudo ./scripts/memory-optimizer.sh

# 2. Verify after reboot
memory-optimizer-verify

# 3. If something goes wrong, rollback
sudo ./scripts/memory-optimizer.sh --rollback /root/memory-optimizer-backups/backup-YYYYMMDD-HHMMSS

Usage

Basic Installation

# Standard installation
sudo ./scripts/memory-optimizer.sh

Dry-Run (Test without changes)

sudo ./scripts/memory-optimizer.sh --dry-run

Force Mode (Override hibernate protection)

sudo ./scripts/memory-optimizer.sh --force

Rollback

# List available backups
sudo ./scripts/memory-optimizer.sh --list-backups

# Rollback to specific backup
sudo ./scripts/memory-optimizer.sh --rollback /path/to/backup

Configuration

RAM Tier Table

RAM ZRAM (RAM/2) Swapfile (ZRAM/2) Effective Total
4GB 2GB 1GB ~11GB
8GB 4GB 2GB ~22GB
16GB 8GB 4GB ~44GB
32GB 16GB 8GB ~88GB
64GB 32GB 16GB ~176GB

Effective total assumes 5:1 ZRAM compression with zstd

Kernel Parameters

Parameter Value Purpose
vm.swappiness 180 Prefer ZRAM over evicting file cache
vm.page-cluster 0 Single page reads (optimal for ZRAM)
vm.vfs_cache_pressure 50 Protect file cache
vm.watermark_scale_factor 125 Early kswapd activation

Files Modified

File Purpose
/etc/sysctl.d/99-memory-optimizer.conf Kernel parameters
/etc/systemd/zram-generator.conf ZRAM configuration
/swapfile Disk swap fallback
/etc/fstab Swapfile mount entry

Verification

After reboot:

# Run verification script
memory-optimizer-verify

# Manual checks
zramctl                           # ZRAM status
swapon --show                     # All swap devices
cat /proc/sys/vm/swappiness       # Should be 180
cat /sys/module/zswap/parameters/enabled  # Should be N or 0

Rollback

Automatic backups are created at /root/memory-optimizer-backups/

# List backups
sudo ./scripts/memory-optimizer.sh --list-backups

# Restore
sudo ./scripts/memory-optimizer.sh --rollback /root/memory-optimizer-backups/backup-20260127-123456

# Reboot after rollback
sudo reboot

Supported Systems

Distributions

  • Fedora, RHEL, CentOS, Rocky, Alma
  • Debian, Ubuntu, Linux Mint, Pop!_OS
  • Arch, Manjaro, EndeavourOS
  • openSUSE

Bootloaders

  • GRUB (grubby)
  • systemd-boot
  • UKI (Unified Kernel Image)

Filesystems

  • ext4, xfs (standard swapfile)
  • btrfs (special handling with NODATACOW)

Troubleshooting

ZRAM not active after reboot

systemctl status systemd-zram-setup@zram0.service
journalctl -u systemd-zram-setup@zram0.service

Swapfile not mounting

# Check fstab entry
grep swapfile /etc/fstab

# Manual activation
sudo swapon /swapfile

System still using ZSWAP

# Check runtime status
cat /sys/module/zswap/parameters/enabled

# Check kernel cmdline
cat /proc/cmdline | grep zswap

Sources

Best Practices (2025-2026):