See 51 on the three master Zee, Desert Eagle, xingcyx's a fantastic set on the number of concurrent users, and to discuss points of great significance. Unclear if the friends of the two concepts must be carefully learned.
Story begins xingcyx's remarks :
Disclaimer: The following Q & A is my experience and based on actual information received through various channels and finishing, the answer mainly represent my personal views, not the standard answer, those who are different opinions, advice welcome criticism.
Q: the number of concurrent users and the collection points are necessarily looking for? Performance test must be used in the collection point to test it?
A: number of concurrent users, by definition, simultaneous users, where the \ is a special case of concurrent, multi-pressure used to test the performance of the system in an instant. Therefore, the number of concurrent users and the collection points are linked, but not necessarily linked, in the test performance of concurrent users testing scenarios , you can not set up a collection point, this will depend on the test objectives and test strategy.
Q: do not set the set point of the test, can represent a \
A: There is a saying, set up collection points is to ensure \ The role is a collection of point tools to control, to ensure that a request to a strict \ However, if the micro view of things, does not exist in the strict sense of the complicated, even if the client by setting the set point the way to 100 requests and submit to the background, after the transmission on the network consumption, they are not likely to arrive at the same time,
ralph lauren polos, And even if the 100 arrives at the server-side requests the same time, by the middleware and applications, various database connection pool, the buffer, CPU processing queue and other restrictions may also have to wait on the server side. Therefore, in the strict sense \ problem.
performance test no more than two purposes, first evaluation, the second is tuning.
in the evaluation for the purpose of performance testing, users are more concerned about the complicated business, which is the case of concurrent real business scenarios, in which case just follow the pattern of business operations to set the scene on it, and not need to set the collection point.
collection point is a special case of concurrent, usually for the purpose of tuning in to the performance test will be used by the aim of targeted performance problems that may exist on a module that pressure to to find performance bottlenecks.
collection point in the actual testing process I used was not much.
Zee:
on the set,
ralph lauren shirts, I always felt that there is no controversy in the past two days to see a few posts talking about this stuff. One thing I think we all agree: the collection is a collection of relatively.
collection is in the production load set on the machine. If we consider the network, middleware, etc. factors. Certainly not to the server the same time point, and that therefore some people hope to achieve on the server side closer to concurrent operation. That this is true concurrency.
I think the first thing to do is to analyze the application system, in the end what you want.
example,
cheap ralph lauren, a URL you want to achieve the purpose of 1000 also requested. This goal is more clear.
collection point in the discussion, when we rarely get something concrete example. This is a little say. To achieve concurrency. I think it should be more specific analysis applications. Again set a target to do. LR not have been discussing how to achieve.
Xingcyx:
because in practice, I often encounter this situation:
testing requirements that the system should support 200 concurrent users.
then we began to measure, record a good script, the next step is performed in the scene, set up a script in the console for 200 concurrent users, the test result is passed or failed. Controversy came at this time: this script If 200 users through the implementation of the test results can be accepted, can say that the system supports 200 concurrent it?
Desert Eagle:
sure to understand the requirements before the test,
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it means \
course, in practice,
ralph lauren polo sale, these requirements to the hands of our tests are not unusual in people in general to come out when the general situation.
example, web system,
ralph lauren shop, you press the 2/5/8 or 2/5/10 to deal with, if the pass to pass, or let developers tune.
Zee:
from the collection point to the simultaneous determination of the number. I think this is one of the most important part is that the conversion of business.
such as user said: Requires 200 concurrent users.
wanted to make sure it is, 200 users what is the ratio of how many people do this, there are many people doing that, by percentage, with a different script to run.
that come to think about customers. He is concerned about 200 users on the server with a URL on the same point, or one the same resources? I think most of the customers do not care. And he wants that I have 200 users online time. Bu Zhiyu people to unacceptable response times. As for how much would be unacceptable. By ordinary people's mental capacity to measure it. And then, or have other saying that 200 people request the same point the same URL or resources, I would like to increase the vuser by calculating the quantity or set of Yes, or the efforts of other ways to close to this goal.
If this time insisted on the server so many concurrent users. I think it can only try to reduce it to a period of time. And do not I think of the business from the start of,
Xingcyx:
upstairs said is the most common case, in which test demands, I will set the scene to test a hybrid, but also is to do different things according to the percentage of users to set.
but there will be other times, not an actual application, may be a development platform, or working engines, it involves the performance of the underlying concept would prefer some may not like this time of the application of general system as a mixed set the scene to test so simple.
Desert Eagle:
the general said, referring to the concurrent number of concurrent operations, rather than the number of concurrent server-side too.