CouchDB query server js call penalties

couch-rewrite-fn-penalties.js

// Tests process switching penalties for calling
// CouchDB query server js functions.

// Requires jQuery

var passes = 50, host="https://cloudwall.cloudant.com/testr/";

function go (msg, url) {
	var pi = $.Deferred(),
	ctr = passes,
	acc = [];
	
	(function chain () {
		var t=Date.now();
		$.ajax({ url:host+url, dataType:"text", cache:false })
		.always(function(){
			acc.push(Date.now()-t);
			if (--ctr) chain();
			else {
				console.log(msg, acc.reduce(function(a,b){return a+b},0) / acc.length);
				pi.resolve();
			}
		});
	})();
	return pi.promise();
}

function cgo (msg, url) {return function(){return go(msg,url);}}

go	 ("Req to file", 	"_design/testr/testr.json")
.then(cgo("Req to view", 	"_design/testr/_view/testr"))
.then(cgo("View through list", 	"_design/testr/_list/testr/testr"))
.then(cgo("View through rewrite","_design/testr/_rewrite/x/testr"));

/* 

//Run in parallel

go("Req to file", 		"_design/testr/testr.json");
go("Req to view", 		"_design/testr/_view/testr");
go("View through list", 	"_design/testr/_list/testr/testr");
go("View through rewrite", 	"_design/testr/_rewrite/x/testr");

*/

/*
Design document json:

{
   "_id": "_design/testr",
   "name": "Test _list switch penalties",
   "lists": {
       "testr": "function (head,req) {\n\t\tstart({\theaders: {'Content-Type': 'application/json'}});\n\t\tsend('{\"total_rows\":0,\"offset\":0,\"rows\":[\\n\\n]}\\n');\n\t}"
   },
   "views": {
       "testr": {
           "map": "function (doc) {\n\t\t\temit (doc._id, null);\n\t\t}"
       }
   },
   "rewrites": [
       {
           "from": "/x/*",
           "to": "../../_design/testr/_view/*"
       }
   ],
   "_attachments": {
       "testr.json": {
           "content_type": "application/json",
					 "data": "eyJ0b3RhbF9yb3dzIjowLCJvZmZzZXQiOjAsInJvd3MiOlsKCl19"
       }
   }
}

*/