I was using a synchronizing timer to best mimic a burst of http requests..... however, running a test I came across an anomaly that made me think I'm doing it incorrectly.
I had a http request to login in users (call it "Login"), then another http request that got something from my web site (call it "ABC"), then another request (the one I'm most interested in -which I'll call "XYZ" -where all users are instantaneously forwarded to another site). I had the number of users and a ramp up time to accommodate for the users to be logged in and to do "ABC". I put a synchronizing timer inside the http request "XYZ" -at the top -within the request. My thought was that users would log in, do "ABC" in good time, then "XYZ" would wait until all users had logged in and done "ABC", and then all users would attempt the sudden burst of "XYZ". I'd run my load tests with no trouble -or so I thought. Then the other day I happened to extend the ramp up time and mysteriously "XYZ" started to fail. It seems counter intuitive; why would providing a longer ramp up time (and well within any timeouts as well, we're talking 30 secs as a ramp up time here instead of 20 seconds) cause failure? I then realized moving the synchronizing timer between http requests would allow for success, rather than leaving it inside (at the top) of the "Xyz" request. I've searched (a lot) of JMeter tutorials and I can't find clarification on this -should the synchronizing timer be outside the http request, and before the request you wish to have a "burst" on? Scratching my head on this.... Thanks.