system.mem.used < 0 in some cases

[alq666]

@conorbranagan this is the bug you saw (lmk if you've filed one already).

[alq666]

Indeed,

'memPhysUsed': 1546

v.

topdog@ip-10-218-95-248:~$ free -m
             total      used       free     shared    buffers     cached 
Mem:         17520      15335       2184          0        247      13355
-/+ buffers/cache:       1732      15788
Swap:            0          0          0

Caused by shared memory?

topdog@ip-10-218-95-248:~$ cat /proc/meminfo 
MemTotal:       17940700 kB
MemFree:         2353908 kB
Buffers:          253840 kB
Cached:         13661944 kB
SwapCached:            0 kB
Active:          6912772 kB
Inactive:        7637420 kB
Active(anon):     437256 kB
Inactive(anon):   390652 kB
Active(file):    6475516 kB
Inactive(file):  7246768 kB
Unevictable:          60 kB
Mlocked:              32 kB
SwapTotal:             0 kB
SwapFree:              0 kB
Dirty:               140 kB
Writeback:             0 kB
AnonPages:        634484 kB
Mapped:           207828 kB
Shmem:            193464 kB
Slab:             438484 kB
SReclaimable:     415820 kB
SUnreclaim:        22664 kB
KernelStack:        1432 kB
PageTables:            0 kB
NFS_Unstable:          0 kB
Bounce:                0 kB
WritebackTmp:          0 kB
CommitLimit:     8970348 kB
Committed_AS:    3102772 kB
VmallocTotal:   34359738367 kB
VmallocUsed:        6564 kB
VmallocChunk:   34359716652 kB
DirectMap4k:    17920000 kB
DirectMap2M:           0 kB