jmeter-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From sebb <seb...@gmail.com>
Subject Re: Performance Test Setup for a web site...
Date Fri, 06 Nov 2009 18:08:07 GMT
On 06/11/2009, Deepak Shetty <shettyd@gmail.com> wrote:
> Hi
>  one of the key problems that I face is simulating varying concurrent usage
>  accurately. e.g. when the day starts out you want this to be low and hit
>  peaks as people come into work and then drop off at lunch or whatever.
>  Specifying different thread groups is one of the ways that you simulate this
>  as you have pointed out.
>  JMeter doesn't have a way to vary thread counts in a thread group easily ,
>  you must setup the total number a priori and then use ramp ups or delays or
>  whatever.
>  Is there are any plans to be able to vary the number of active threads in
>  the threadgroup at runtime?
>  regards

Probably not in the next release, but perhaps after that.

You can use the Constant Throughput Timer in conjunction with a
variable in order to vary the load, see for example:

http://jakarta.apache.org/jmeter/usermanual/best-practices.html#beanshell_server

I've used that in performance tests that ran over many hours.

> deepak
>
>
>  On Fri, Nov 6, 2009 at 6:54 AM, Carl Shaulis <cshaulis@homeaway.com> wrote:
>
>  > Getting proportional scripts I can think of two approaches:
>  > 1.  Scrap a days worth of log files for all of the requests coming to your
>  > application servers then replay these requests using JMeter
>  > 2.  Estimate what portion of your community does what, then use various
>  > thread groups to emulate this traffic (Thread group one (ie-visit home
>  > page)
>  > 50%, ThreadGroup2 (ie. - Search) 40% etc...
>  >
>  > Number of virtual threads really is dependent on a combination of your load
>  > servers and your target.  For example we have a 16 core machine as a load
>  > generator and a an equivalent machine supporting our application.  Using
>  > 100
>  > concurrent threads and no sleeps the load machine was less than 10% CPU
>  > utilization and the target machine was at 90% CPU utilization.  When then
>  > cached a bunch of the requests and the target machine could respond faster
>  > than the load machine so the Load machine CPU was stressed at the same
>  > thread count, additionally we were almost at our bandwidth limits.  So
>  > Deepak is spot on saying monitor machine resources.
>  >
>  > We have had success using MySQL to inspect data, but we have also kept our
>  > load times brief (5 minutes).  If using a linux box to collect your data
>  > you
>  > can get a quick evaluation of throughput by using wc -l <filename> divided
>  > by the test duration to give you TPS.
>  >
>  > Good luck!
>  >
>  > Carl
>  >
>  >
>  > On 11/6/09 1:13 AM, "Deepak Shetty" <shettyd@gmail.com> wrote:
>  >
>  > >> I will create Scripts which will hit the site pages proportional to
>  > there
>  > > usage
>  > > This isnt easy.
>  > >
>  > >> - What should be the configuration of the machine which will simulate
>  > these
>  > >> - If more then one test machine is required please specify there
>  > > configuration?
>  > >> - How many instances of jMeter we need to run for simulating 5000 users?
>  > > My preference is Multiple low end machines running separate JMeter
>  > instances
>  > > to 1 big machine. It simulates the network better . The load you can
>  > > generate depends on what else is running and what your tests actually do.
>  > > People have reported running 1000 threads from a single machine. In any
>  > case
>  > > , you must generate a load and check your client machine resources ,
>  > > preferably the cpu shouldn't exceed 60-80% and memory used should all be
>  > RAM
>  > > not virtual. You can increase the number of threads till you hit some
>  > limit
>  > > after which the client machine may become a bottleneck and give you
>  > > incorrect results.
>  > > See related
>  > > http://wiki.apache.org/jakarta-jmeter/HowManyThreads
>  > >
>  > http://jakarta.apache.org/jmeter/usermanual/best-practices.html#lean_mean
>  > > When running multiple jmeter instances you can either run each instance
>  > > separately (my preference) or you can run Jmeter  in master slave (this
>  > is
>  > > more inefficient , check the mail archives).
>  > >
>  > >> How the result file output should be consolidated from various scripts?
>  > If
>  > >> someone is using any tool for consolidating the output files please
>  > share
>  > >> information regarding the same.
>  > >> - Is there any tool for converting these files to some reports. I have
>  > > heard
>  > >> that reports can be generated using some available xslt's in ant. But
>  > that
>  > >> does not work with large output files. So please suggest alternatives.
>  > > I assume you mean combining the results if you run jmeter instances
>  > > separately. if you use CSV as your format, just concatenate. Mostly if
>  > you
>  > > have long running tests , you would load the CSV files into a database
>  > > table. You have some listeners that can read the CSV/JTL files , but
>  > you'd
>  > > have to use a listener whose memory utlization is constant and not
>  > > proportional  to number of samples (e.g. summary report -
>  > > http://jakarta.apache.org/jmeter/usermanual/component_reference.htmlsection
>  > > 18.3).
>  > >
>  > > regards
>  > > deepak
>  > >
>  > >
>  > > On Thu, Nov 5, 2009 at 2:54 PM, Harry_ <harjitworks@gmail.com> wrote:
>  > >
>  > >>
>  > >> Hi,
>  > >>
>  > >> We need to do performance testing for our website simulating 5000 users
>  > >> using jmeter and other open source tools. The following information is
>  > with
>  > >> us:
>  > >>
>  > >> - A csv file containing links and number of times that link last month.
>  > The
>  > >> file is sorted according to popularity of page visited.
>  > >> - With this file I can get information about average number of hits per
>  > >> unit
>  > >> time say per minute. (estimate can be made regarding max load, min
>  > load). I
>  > >> will create Scripts which will hit the site pages proportional to there
>  > >> usage.
>  > >> - All the requests will be http requests.
>  > >> - Average size of the page will be 350 KB (including embedded objects
>  > >> within
>  > >> the page).
>  > >>
>  > >> Now we need answer to the following questions:
>  > >>
>  > >> - How should performance testing of the site simulating that much user
>  > load
>  > >> using Jmeter should be done?
>  > >> - What should be the configuration of the machine which will simulate
>  > these
>  > >> many users? (Someone suggested me 8 core@3 GHz, 16 GB machine).
>  > >> - If more then one test machine is required please specify there
>  > >> configuration?
>  > >> - How many instances of jMeter we need to run for simulating 5000 users?
>  > >> - How the result file output should be consolidated from various
>  > scripts?
>  > >> If
>  > >> someone is using any tool for consolidating the output files please
>  > share
>  > >> information regarding the same.
>  > >> - Is there any tool for converting these files to some reports. I have
>  > >> heard
>  > >> that reports can be generated using some available xslt's in ant. But
>  > that
>  > >> does not work with large output files. So please suggest alternatives.
>  > >> - What other things should i keep in mind for doing the performance
>  > test?
>  > >>
>  > >> We would appreciate if someone can answer these queries based on there
>  > >> experience. .
>  > >>
>  > >> Thanks,
>  > >> Harry
>  > >> --
>  > >> View this message in context:
>  > >>
>  > http://old.nabble.com/Performance-Test-Setup-for-a-web-site...-tp26223743p262
>  > >> 23743.html
>  > >> Sent from the JMeter - User mailing list archive at Nabble.com.
>  > >>
>  > >>
>  > >> ---------------------------------------------------------------------
>  > >> To unsubscribe, e-mail: jmeter-user-unsubscribe@jakarta.apache.org
>  > >> For additional commands, e-mail: jmeter-user-help@jakarta.apache.org
>  > >>
>  > >>
>  >
>  >
>  > ---------------------------------------------------------------------
>  > To unsubscribe, e-mail: jmeter-user-unsubscribe@jakarta.apache.org
>  > For additional commands, e-mail: jmeter-user-help@jakarta.apache.org
>  >
>  >
>

---------------------------------------------------------------------
To unsubscribe, e-mail: jmeter-user-unsubscribe@jakarta.apache.org
For additional commands, e-mail: jmeter-user-help@jakarta.apache.org


Mime
View raw message