I'm just wondering how MongoDB handles memory. The machines I'm
running it on have 48GB, which based on our current DB size should be
more than enough:
SECONDARY> db.stats()
{
"db" : "master",
"collections" : 118,
"objects" : 51167677,
"avgObjSize" : 132.34001809384466,
"dataSize" : 6771531300,
"storageSize" :
8493039616,
"numExtents" : 722,
"indexes" : 564,
"indexSize" : 9511279792,
"fileSize" : 23544725504,
"nsSizeMB" : 16,
"ok" : 1
}
But I got a warning email from our monitoring system that it was using
almost *all* the available system memory:
MONGODB WARNING - Memory Usage: 42.05GB resident, 101.26GB mapped,
46.13GB virtual
Can someone explain what's going on here?