numa_set_distance(9)

🎀 NAME 🎀

Okay bestie, meet numa_set_distance(9) from the Kernel API Manual — she sets the NUMA distance from one NUMA to another. Literally her whole job. 💅

✨ SYNOPSIS ✨

void numa_set_distance (int from , int to , int distance );

🌸 ARGUMENTS 🌸

• from — the 'from' node to set distance 💖
• to — the 'to' node to set distance 🫶
• distance — the NUMA distance ✨

💅 DESCRIPTION 💅

Okay so the main character move: set the distance from node from to to to distance. That's it, that's the vibe. 👑

If the distance table doesn't exist yet, one that's large enough to accommodate all the currently known nodes will be created. Slay, built on demand.

If that table can't be allocated, a warning is printed, and further calls are ignored until the distance table is reset with numa_reset_distance. No cap, that's the rule — warning first, then the silent treatment for later calls. 😭

If from or to is higher than the highest known node or lower than zero at the time of table creation, or distance doesn't make sense, the call is ignored. This is to allow simplification of specific NUMA config implementations. So if the args are giving nonsense, she just doesn't. 🙈

🦋 SEE ALSO 🦋

• Kernel file: ./mm/numa_memblks.c
• numa_reset_distance(9)
• numa_remove_memblk_from(9)
• numa_move_tail_memblk(9)
• numa_add_memblk(9)
• numa_add_reserved_memblk(9)
• numa_cleanup_meminfo(9)
• numa_fill_memblks(9)

🫶 that's the page, bestie! source/version + date stamp: ./mm — October 2026. periodt. 💖