title: Is it ideal that MongoDB is using 150 MB memory?
body: <p>This is the first project by me which is using MongoDB.</p>
  
  <p>I have hosted it on a linode (a VPS which uses XEN) and I'm checking memory usage with "top".</p>
  
  <p>The mongod process seem to use around 150 MB of memory. There were no connections to it when I checked. I use RockMongo to administer it. My main database stats are -</p>
  
  <pre><code>Size - 464m 
  Storage Size - 83.99m
  Data Size - 66.4m
  Index Size - 49.33m
  Collections - 5
  Objects - 584850
  </code></pre>
  
  <p>A lot of queries happen when the cron job is running, around 75 per minute or even more. But, as I said earlier, when I checked the memory usage, there were no connections.</p>
  
  <p>Output of <code>db.serverStatus();</code></p>
  
  <p>Note - I had restarted mongod before running <code>db.serverStatus();</code> and the memory usage was 40 MB.</p>
  
  <pre><code>{
     "retval": {
       "version": "1.6.5",
       "uptime": 790,
       "uptimeEstimate": 783,
       "localTime": "Mon, 07 Feb 2011 00: 51: 04 -0500",
       "globalLock": {
         "totalTime": 790027671,
         "lockTime": 376381,
         "ratio": 0.00047641495838188,
         "currentQueue": {
           "total": 0,
           "readers": 0,
           "writers": 0
        }
      },
       "mem": {
         "bits": 64,
         "resident": 38,
         "virtual": 957,
         "supported": true,
         "mapped": 288
      },
       "connections": {
         "current": 2,
         "available": 9598
      },
       "extra_info": {
         "note": "fields vary by platform",
         "heap_usage_bytes": 152448,
         "page_faults": 0
      },
       "indexCounters": {
         "btree": {
           "accesses": 1,
           "hits": 1,
           "misses": 0,
           "resets": 0,
           "missRatio": 0
        }
      },
       "backgroundFlushing": {
         "flushes": 13,
         "total_ms": 1,
         "average_ms": 0.076923076923077,
         "last_ms": 0,
         "last_finished": "Mon, 07 Feb 2011 00: 50: 54 -0500"
      },
       "cursors": {
         "totalOpen": 0,
         "clientCursors_size": 0,
         "timedOut": 0
      },
       "opcounters": {
         "insert": 0,
         "query": 57,
         "update": 0,
         "delete": 0,
         "getmore": 0,
         "command": 46
      },
       "asserts": {
         "regular": 0,
         "warning": 0,
         "msg": 0,
         "user": 0,
         "rollovers": 0
      },
       "ok": 1
    },
     "ok": 1
  }
  </code></pre>
  
  <p>A friend of mine runs his WordPress blog on a linode with same amount of ram (1024 MB). His MySQL usage show mere 20.48 and approx. 12 users are like "always-surfing" (as in always-on) on his site.</p>
  
  <p>This makes me feel MongoDB isn't a nice choice for me and I should have sticked to MySQL!</p>
  
  <p>Thank you, all.</p>