Enabling HugePage for PostgreSQL

Enabling HugePage for PostgreSQL to reduce memory fragmentation and improve performance.

Use node_hugepage_count and node_hugepage_ratio or /pg/bin/pg-tune-hugepage

To enable HugePages, consider node_hugepage_count and node_hugepage_ratio. Apply these settings with ./node.yml -t node_tune.

HugePages have advantages and disadvantages for databases. Exclusive memory management prevents reallocation and reduces database OOM risk. However, HugePages can reduce performance in some conditions.

Before PostgreSQL starts, allocate enough huge pages. The pg-tune-hugepage script can reclaim the unused portion. This script is available only for PostgreSQL 15+.

If PostgreSQL is already running, use this method to enable huge pages. It requires PG15+:

sync; echo 3 > /proc/sys/vm/drop_caches   # Flush disk, release system cache (be prepared for database perf impact)
sudo /pg/bin/pg-tune-hugepage             # Write nr_hugepages to /etc/sysctl.d/hugepage.conf
pg restart <cls>                          # Restart postgres to use hugepage