JMeter

Jmeter >	used for load Testing & Stress testing, under testing strategy called Performance Testing.	JMeter is a pure Java desktop application. It requires a fully compliant JVM 6 or higher. You need to download and install the Jdk8 version of Java SE Development Kit or Amazon Corretto 1.8 which is equivalent to Java 8.	1. Go for Test Plan in JMeter 2. Add Thread Group (number of Users, total time to complete all threads, number of time such requests repeates) and 3. Add Sampler (Http Request) 4. Add Assertion if any and Add Listener (single or mutiple) 5. Click on run. Request goes to server and response recorded in Listener. 6. Results can be analyse in the form of graphs, tables, tree etc
		Test Plan :-	Run Thread Groups consecutively – one at a time
			Run tearDown Thread Groups – this thread will run after the main test execution.	The tearDown feature is generally used for reporting or cleaning operations – It’s similar to a normal Thread Group but executes post-test activities, such as cleaning up test data or restoring the system to its initial state.	Two test plan can be combined with merge option
		Thread Group :-	Thread Groups is a collection of Threads. Each thread represents one user. Simulates number of users requesting to server	Number of Threads = number of users, Ramp-up period = total time to take to make all thread up & running – total seconds/total threads = time at which each thread start after the previous one, Loop count = number of times request sent by each user	select Same user on each iteration, ( If 10 threads are used, and the ramp-up period is 100 seconds, then JMeter will take 100 seconds to get all 10 threads up and running. Each thread will start 10 (100/10) seconds after the previous thread was begun.)
		Samplers :-	FTP Request > Download or Upload File
			HTTP Request > In Response, Receive HTML or Image/data from website
			JDBC Request > Send SQL query & receive result	(Java Datatbase Connectivity)
			SMTP Sampler > Test Mail server by sending mails	(Simple Mail Transfer Protocol)
			Access Log Sampler > gets an access log file which records the requests users make to the a web application. Usually, each entry in the Access Log contains a server address, a user machine address, a request, a corresponding timestamp and a response code with a response message.
		Assertions :-	Verifies that server under test returns the expected result :-	Response Assertion >	Main sample and sub-samples > Response Code > contains > 200
				Duration Assertion
				Size Assertion
				Xml Assertion
				HTML Assertion
		Config Elements :-	Setup defaults or variables for samplers :-
				CSV Data Set Config > Jmeter read lines from text file and split them into variables
				HTTP Cookie Manager > act like browser cookie. It store cookie use that to send HTTP request to server wrt that specific user
				Login Config Element > add username & password in sampler
				HTTP Request Defaults > have server parameters/query Params to send HTTP requests
		Listeners :-	Shows the result of test execution in formats like Tree, Table, Graph or Log file. :-	Tree > show user request in basic HTML format
				Table > show result in table
				Graph > show result in graphical form
				Log file > show result in text file
				Miliseconds (Time Duration)	Miliseconds (Actual Action Duration)
		Load time >	Time between just before sending the request to just after receiving the last part of the response. (A)	785	45	< Response fetched in (A) – (B)
		Latency >	Time between just before sending the request to just after receiving the first part of the response (B)	740	518	< Actual Latency by less connect time (B) – (C)
		Connect time >	measures the time it took to establish the connection, including SSL handshake. Note that connect time is not automatically subtracted from latency. (C)	222
		Size in bytes :	Header Size + Body Size	20781	20781	(D) + (E)
		Header Size : in bytes	Headers contain url, Payload (user data), client data (OS, Browser data, proxy data), token, querryParam, Response Header ( contains Server Location, Cookies) (D)	1209
		Body Size : in bytes	User Inputa data, Response body data contains result, Json like Image/pdf etc in encryted format (E)	19572
		Sent bytes	that data a client sends to a server when making a request	119
		Median	It is the Value under which 90 Percent of the examples fall. like 90% call complete in this miliseconds	792
		Average	It is used to specify how much time is taken by a specific request. Time (miliseconds) taken on average to complete API Call	930				Elapsed time = ramp up time ?
		Throughput	Number of request handles / minute	391.7/minutes OR	6.52 / seconds	Throughput in seconds * Elapsed time = Total number of User	6.5 * 30 = 200 Users	no. of request/Elapsed time (ms) * 1000  = throughput/sec =>	6.67
		Latest Sample	Time taken to complete call by last sample in test plan	775
		Deviation (from load time)	Diff. from set value in miliseconds, If the deviation value is low, it means the system is not under stress. It is basically the more time taken by api call from set value in seconds. Deviation shows how much the server response time varies, a measure of degree of dispersion	392
		Thread vs sample	Thread is number of users & sample is total number of request made by users