Time difference between Elasticsearch "took" and that calculated manually

Question

I can't figure out why is there such a difference between ES time and the query time.

var url = "192.168.100.11:9200";
var elasticsearch = require('elasticsearch');

var client = new elasticsearch.Client({
    host: url
});
var accounts = [];   
var startTime = new Date();
client.search({"index":"test", "type":"testdata1", searchType:"count"}).then(
    function (searchData) {
        var endDate = new Date();
        console.log(" total time : [" + (endDate - startTime) + "]")
        console.log(" ES   >>>>> :" + JSON.stringify(searchData.took));
    }).catch(function (err) {
        console.log(" errr  >>>> :" + err);
    });

Output:

total time : [37]

ES >>>>> :2

As you can see, es result took shows query was executed in 2 ms, but if I calculate total time taken to run in code , it took 37ms. What took 35ms ?

Answer 1

According to this thread, the 'took' value measures wall time of query execution in Elasticsearch, which includes queue waiting time but excludes

• serializing the request into JSON on the client
• sending the request over the network
• deserializing the request from JSON on the server
• serializing the response into JSON on the server
• sending the response over the network
• deserializing the response from JSON on the client