Load testing

Load Testing:Load testing is a part of performance testing. It is used to validate the system performance under varying loads at different time levels that are anticipated during production operations.Normally Load is nothing but the no of requests which will attack the server. In simple terms, if 100k people from all over the globe are using www.mail.yahoo.com at the same time, and trying to upload their photos in through attachment option in yahoo.mail.com, then it is obvious that the system will slow down and it takes couple of mins more to finish the transaction than it takes normally. It is because 100k client requests attacked the server at the same time and since the server can not process 100k requests at a time and probably it may put some for the requests in queue until it finishes the previous requests. So, performance engineers observe and note the time it takes to finish the upload attachment transaction. Now we apply a load of 200k requests at the same time to the server for the same transaction of upload attachment in mail.yahoo.com. So, this time the server takes some more extra time to process the requests and give response back. In this way, performance engineers apply different varying load gradually at frequent intervals and observe the response times of server and analyze the results and prepare a report of the behavior of the server at different loads. Then if they found that the response times are degraded too high, then they will investigate the problem along with the database administrators, web server & application server admistrators together and analyze the logs which are generated in web servers, application servers & database servers to resolve the issue and find out the bottlenecks.