Want to improve the performance of your Facebook Graph API calls? Try trimming your requests down to just the information you need. During recent optimization and testing of some Facebook Graph API client code my colleague Bob determined just how much time could be saved by tuning the API requests. Typical requests result in the return of a default object, for example this URL
https://graph.facebook.com/6547384565867889
returns this album object:
{
"id": "6547384565867889",
"from": {
"name": "John Doe",
"id": "9834439837"
},
"name": "Mobile Uploads",
"link": "https://www.facebook.com/album.php?fbid=6547384565867889&id=9834439837&aid=743987489",
"cover_photo": "748397943639",
"privacy": "custom",
"count": 1,
"type": "album",
"created_time": "2011-11-24T16:04:54+0000",
"updated_time": "2011-11-24T16:04:55+0000",
"can_upload": false
}
The client application doesn't need most of this information, all it needs are the id, name, photo count, and when it was created. By adding the optional fields parameter with a comma separated list of field names to the request:
https://graph.facebook.com/6547384565867889?fields=id,name,count,created_time
an object with only the requested information is returned (apparently Facebook gives us "type" for free):
{
"id": "6547384565867889",
"name": "Mobile Uploads",
"count": 1,
"created_time": "2011-11-24T16:04:54+0000",
"type": "album"
}
Not only does this result in less information being transmitted to the client, more importantly it results in considerably shorter response times from Facebook. It seems that retrieving this information requires significant lookup effort on Facebook's servers and asking for less information means less rummaging through the datastore for all the bits. Bob found that getting 57 albums containing 2,434 photos from his account using the default request took 90 seconds. After adding the fields parameter with only the fields required it took only 40 seconds, less than half the original time! Of course YMMV based on the network, we also found that eliminating likes and comments had the largest effect in reducing response time. If you are working on an application that gets large amounts of data from Facebook it may be worth the effort to consider what information is being provided and only get what the client needs.
