Not sure how its calculating things:
ps aux|grep node
kibana 17468 0.9 11.7 1314596 459236 pts/0 Sl 13:20 0:25 /opt/kibana/bin/../node/bin/node --expose-gc --trace-gc --trace-gc-verbose --max-old-space-size=200 /opt/kibana/bin/../src/cli
so as you can see the setting is 200M, the size of node is currently ~ 450M
the stdout file shows:
[17468] 2514028 ms: Scavenge 120.5 (162.5) -> 111.5 (165.5) MB, 13.6 ms [allocation failure].
[17468] Memory allocator, used: 169444 KB, available: 100892 KB
[17468] New space, used: 3467 KB, available: 12916 KB, committed: 32768 KB
[17468] Old pointers, used: 70437 KB, available: 0 KB, committed: 72446 KB
[17468] Old data space, used: 27191 KB, available: 308 KB, committed: 28409 KB
[17468] Code space, used: 10659 KB, available: 11011 KB, committed: 21912 KB
[17468] Map space, used: 2252 KB, available: 5696 KB, committed: 8190 KB
[17468] Cell space, used: 110 KB, available: 12 KB, committed: 128 KB
[17468] PropertyCell space, used: 56 KB, available: 7 KB, committed: 64 KB
[17468] Large object space, used: 0 KB, available: 99851 KB, committed: 0 KB
[17468] All spaces, used: 114175 KB, available: 29952 KB, committed: 163917 KB
[17468] External memory reported: -188 KB
[17468] Total time spent in GC : 447.7 ms
[17468] 2654927 ms: Scavenge 124.2 (165.5) -> 115.2 (168.5) MB, 12.9 ms [allocation failure].
[17468] Memory allocator, used: 172516 KB, available: 97820 KB
[17468] New space, used: 3474 KB, available: 12909 KB, committed: 32768 KB
[17468] Old pointers, used: 73505 KB, available: 0 KB, committed: 75469 KB
[17468] Old data space, used: 27778 KB, available: 149 KB, committed: 28409 KB
[17468] Code space, used: 10698 KB, available: 10971 KB, committed: 21912 KB
[17468] Map space, used: 2321 KB, available: 5628 KB, committed: 8190 KB
[17468] Cell space, used: 110 KB, available: 12 KB, committed: 128 KB
[17468] PropertyCell space, used: 56 KB, available: 7 KB, committed: 64 KB
[17468] Large object space, used: 0 KB, available: 96779 KB, committed: 0 KB
[17468] All spaces, used: 117945 KB, available: 29679 KB, committed: 166940 KB
[17468] External memory reported: -201 KB
[17468] Total time spent in GC : 460.6 ms
And it thinks there is space in the "old data space remaining"