This is with standard Armbian Debian GNU/Linux 8 (jessie) 3.4.112-sun8i at the stock 1.296GHz CPU speed, and there is a fan+heatsink to stop overheating. I've disabled swap.
# memtester 239 5 is OK, while # memtester 240 5 crashes out almost immediately:
[10933.657662] Out of memory: Kill process 17061 (memtester) score 89 or sacrifice child
[10933.657673] Killed process 17061 (memtester) total-vm:246992kB, anon-rss:245380kB, file-rss:28kB
If I enable a small 32MB swap file, memtester seems to work fine up to 1200MB (still 750MB reported free, and no swap used) and crashes out for any larger values?? I'm getting the same out of memory problems trying to run the hpcc (Linpack) benchmark - very small values of N work, but anything larger gets killed with out of memory.
I never got these errors using Raspbian/Debian Jessie 8.4 on the Raspberry Pi Zero/3 or NanoPC-T3 boards (all with swap disabled).
Any suggestions much appreciated! Thanks