⚙️ MariaDB InnoDB Tuning — VM 16 Core / 32 GB RAM

🧭 Tujuan

Optimasi performa InnoDB buffer pool agar mengurangi Innodb_buffer_pool_wait_free (menunggu flush karena buffer pool penuh), meningkatkan efisiensi memori, dan mempercepat query.

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💾 1. Buffer Pool Size

Kondisi Server	Rekomendasi	Catatan
Dedicated DB server	innodb_buffer_pool_size = 24G	~75% total RAM
DB + App (shared)	innodb_buffer_pool_size = 16G	~50% total RAM

🧠 Gunakan 60–75% RAM untuk buffer pool jika MariaDB adalah satu-satunya service utama.

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🧩 2. Buffer Pool Instances

Buffer Pool Size	Instances Ideal	Contoh
1–4 GB	2	Kecil
8–16 GB	4	Sedang
24–64 GB	8	Besar (cocok untuk 24G)

Setiap instance bekerja paralel di multi-core. Hindari terlalu banyak karena menambah overhead memori.

innodb_buffer_pool_instances = 8

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⚙️ 3. Disk I/O Capacity

Jenis Disk	innodb_io_capacity	innodb_io_capacity_max
HDD	200	400
SSD / NVMe	2000	4000

Untuk VM modern (SSD/NVMe) gunakan nilai tinggi agar flush halaman kotor bisa cepat.

innodb_io_capacity = 2000
innodb_io_capacity_max = 4000

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🔧 4. Parameter Pelengkap

innodb_flush_method = O_DIRECT
innodb_flush_neighbors = 0
innodb_max_dirty_pages_pct = 75
innodb_lru_scan_depth = 2048

Penjelasan:

• O_DIRECT → Hindari double buffering (RAM OS & MariaDB).
• flush_neighbors=0 → Lebih efisien di SSD (tidak flush tetangga).
• max_dirty_pages_pct=75 → Flush lebih dini, hindari penumpukan.
• lru_scan_depth → Kontrol agresivitas pembersihan cache.

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🧠 5. Contoh Konfigurasi Lengkap (/etc/mysql/my.cnf)

[mysqld]
# InnoDB Memory & Cache
innodb_buffer_pool_size = 24G
innodb_buffer_pool_instances = 8
innodb_flush_method = O_DIRECT
innodb_flush_neighbors = 0
innodb_max_dirty_pages_pct = 75
innodb_lru_scan_depth = 2048

# I/O Optimization
innodb_io_capacity = 2000
innodb_io_capacity_max = 4000

# Threads (opsional, untuk 16 core)
innodb_read_io_threads = 8
innodb_write_io_threads = 8
innodb_purge_threads = 4

# Log & Flush Settings
innodb_log_file_size = 2G
innodb_log_buffer_size = 512M
innodb_flush_log_at_trx_commit = 1

# Monitoring
innodb_monitor_enable = all

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🔍 6. Verifikasi

Cek status buffer pool:

SHOW GLOBAL STATUS LIKE 'Innodb_buffer_pool_wait_free';
SHOW GLOBAL STATUS LIKE 'Innodb_buffer_pool_pages_free';
SHOW GLOBAL STATUS LIKE 'Innodb_buffer_pool_pages_dirty';

Jalankan dua kali (selang beberapa menit):

• Jika Innodb_buffer_pool_wait_free tidak bertambah signifikan → konfigurasi sudah ideal ✅
• Jika naik cepat → tambahkan innodb_buffer_pool_size atau optimalkan disk I/O.

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📊 7. Tips Monitoring

Buat interval check sederhana:

watch -n 60 "mysql -e \"SHOW GLOBAL STATUS LIKE 'Innodb_buffer_pool_wait_free';\""

Atau gunakan Prometheus + Grafana untuk visualisasi tren buffer pool metrics.

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🧩 8. Quick Summary

Parameter	Nilai Ideal	Fungsi
innodb_buffer_pool_size	24G	Cache data & index
innodb_buffer_pool_instances	8	Parallel buffer access
innodb_io_capacity	2000	Flush rate
innodb_flush_method	O_DIRECT	Hindari double cache
innodb_flush_neighbors	0	Optimasi SSD
innodb_max_dirty_pages_pct	75	Flush balance
innodb_lru_scan_depth	2048	Cache cleaning depth