Discussions

Performance and scalability: Load Testing effect on LAN

  1. Load Testing effect on LAN (3 messages)

    Hi,
      If Iam doing Load testing for 150 concurrent users on a huge data , Will it effect the LAN?
      The DB Server is seperate, App server is seperate.
      Pls note that we are having other appliccations running
      on other Servers.
      We observered that the Other Application performance is effecting while doing Load Testing of a particular Application which is 8MB ear deployed on seperate server (DB Server is also Seperate).
     All Servers and client M/Cs are in one Net work

      Any help or suggestion in this regards are highly appreciated.

    Thanks a lot in advance

    B S Reddy
  2. Load Testing effect on LAN[ Go to top ]

    hi,

    short answer is yes because of http/https requests traffic. To monitor LAN there are tools for this like http://www.paessler.com/prtg/?banner=PAECOM_SEO.

    hope this helps,

    Bhagvan K
    http://www.architectcorner.com
  3. Hi,  If Iam doing Load testing for 150 concurrent users on a huge data , Will it effect the LAN?  The DB Server is seperate, App server is seperate.  Pls note that we are having other appliccations running   on other Servers.  We observered that the Other Application performance is effecting while doing Load Testing of a particular Application which is 8MB ear deployed on seperate server (DB Server is also Seperate). All Servers and client M/Cs are in one Net work  Any help or suggestion in this regards are highly appreciated.Thanks a lot in advanceB S Reddy
    First of all, you shouldn't perform load testing in production machines, because you are going to degrade the response time perceived by end users.

    If you cannot afford a separate environment, you should watch the network metrics that usually get recollected with the load testing tool. For example, with Mercury LoadRunner, you have a specific report of network metrics that is called 'throughput report'. Other tools, such as Quest PerformaSure have detailed 3-D information, showing the bytes send and received between all the machines of the cluster (application servers, database servers, load testing servers, etc.).

    If your load testing tool does not provide you with information, you may use a separate sniffer tool, or maybe, you can use the tools provided with the operating system. In this link, you may learn how to use 'netstat':

    http://www.cymru.com/Documents/Sun/netstat-k-stats.txt


    Jose Ramon Huerga
    http://www.terra.es/personal/jrhuerga
  4. Load Testing effect on LAN[ Go to top ]

    your question is about the effect on the lan?
    You can do a rough estimate.

    But some questions first: (lower layers)

    Are you on ethernet or other tech? (ethernet degrades faster than token-based lans)
    Is it gigabit/s, 100Mbps, 10 Mbps?
    If ethernet, are they all on same ethernet broadcast segment (hub) or on a switch? (switch will be more efficient, buffers and reduce/eliminate collisions.)

    Is the huge traffic going to or coming from few unique point? (megs going to many clients will not lead to collisions on a switch, but megs from many clients to unique server could.)

    if 150 concurrent users are using what bandwith? You say huge but not saturated.
    I guess gigabit ethernet can transport to 1 meg/s for 150 users, without being saturated. But once saturated, sure the other applications will bottleneck at the network card... hopefully the server you want to load-test.

    So you should check first how much bandwidth left you have before load test. You substract what you see (sniffers) from a fraction of the nominal capacity of your lan: for switched ethernet, there is to many variables, but for single segment (hub), that's about 30% of nominal capacity. (after that, too many collisions and retransmits.)