LoadRunner Upload – Download file / Operative System 4 GB Memory Limitation

Each operating system has a physical memory limit which reciprocally define the boundaries for memory and address space that can be used by the processes, services, objects and services executed over the current operative system version.

Following is the memory limits that are present in Windows OS and how it affects the mdrv.exe process emulation when uploading/downloading large files, generating a reaction where the mdrv will crash, hangs or result in a memory violation.

 The implementation of LR file uploading/downloading is not optimized for huge file. It always reads all the files to memory before upload. That means, for files with 1 GB in size, mdrv has to   obtain 1 GB sequential memory space in the process for each Vuser. However, mdrv is a 32 bit process. In windows system, a 32 bit process has at most 4 GB in memory space, and only 2 GB of them can be used by developer. If the user tries to upload a file with 2 GB in size, it is almost impossible to find proper memory for it, since the other functions will also use some memory.

When the file size is smaller, like 500 MB to 1 GB, it will be possible to make the upload successful. But when we run the script in controller, we should make the Vuser run in process mode.

From the Operating System perspective and as a workaround it is possible to switch the memory use and memory address space allocation to 3 GB for the application and less 1 GB for the operating system.

In order to increase the memory and address space to 3 GB limit we need to be implement the following steps.

  1. Right-click on the Command Prompt icon in the Accessories program group of the Start menu. Click Run as Administrator.
  2. At the command prompt, enter:

bcdedit /set IncreaseUserVa 3072

  1. Restart the computer.
  2. Run the script one more time in VuGen and in the Controller using the LG as process.

For disabling  the  memory increase here is the command.

  1. Right-click on the Command Prompt icon in the Accessories program group of the Start menu. Click Run as Administrator.
  2. At the command prompt, enter:

bcdedit /deletevalue IncreaseUserVa

  1. Restart the computer.

Error -27732: Internal Error – can’t get initial credentials for username/password

The following error appears in web based protocol replay:

Error -27732: Internal Error – can’t get initial credentials for username/password

Wrong configuration of the required elements to make the script replay while using Kerberos authentication

Wrong username password:

  1. In the script go to the web_set_user function
  2. Verify that the username and password specified are correct

Wrong KDC IP:

  1. Open the windows environment settings
  2. Check the krb5.ini location specified in KRB5_COFIG
  3. Open the krb5.ini in an editor
  4. Check the KDC IP specified is as seen in wireshark recording of the application

Error -27732: Internal Error – can’t parse username

The following error message appears during the replay of web based script:

Error -27732: Internal Error – can’t parse username

The KRB5_CONFIG was defined under the System variables. Currently only exact path name is supported.

  1. Open the Windows’ Environment Variables
  2. Search for KRB5_CONFIG in System variables
  3. Verify the path is exact (For example don’t use %windir%)
  4. Correct and save the file path
  5. Restart VuGen

Not able to start LR agent process with multiple terminal session

Not able to start LR agent process with multiple terminal session

Error logs while trying to start second Agent, just can start one Agent:
Error: Communication error: Failed to bind socket while calling bind function. [MsgId: MERR-10344]
19/02/2013 09:20:05 Error: Two Way Communication Error: Function two_way_comm_create_acceptor failed. [MsgId: MERR-60999]

Get inside agent configuration and click the check box for “Terminal Services”.  Not needed to use the Terminal Services side in the Controller, but it needs to be checked on the load generators.

Record IE 11 with Web (HTTP/HTML) protocol using TLS 1.1/1. 2 in VuGen 11.52

A hot fix has been created to enable:

  1. recording of Internet Explorer 11 and
  2. adding TLS 1.1 and TLS 1.2 support in VuGen 11.52

It can be downloaded using the below link: Download hotfix

Please follow the steps below to apply the hotfix:

  1. Go to the installation folder of LoadRunner, VuGen or Performance Center host
  2. Backup the original files in the bin and dat folders.
  3. Copy the hotfix files to the bin and dat folders respectively and replace the original files.
  4. Restart VuGen and try recording the business process in Internet Explorer 11 with TLS 1.1 and TLS 1.2 enabled in Internet Explorer Advanced Options.

Please note that the patch is needed for recording and should not be installed on Load Generator standalone machines.

LoadRunner Error: Data at the root level is invalid

The following error is received when an attempt for a manual correlation of a value is made:

Error: Data at the root level is invalid. Line 1, position 1

The issue is caused by some snapshots containing an invalid XML code. This causes an exception and fails the correlation process.

The issue is fixed in VuGen 12.50. For VuGen 12.02, use the following fix:

  1. Download the attached CorrelationBackEnd.dll
  2. Backup the CorrelationBackEnd.dll in <vugen_installation_folder>\bin directory
  3. Replace with the downloaded one

Service Virtualization monitors are not displayed in the online run screen in Performance Center

Service Virtualization monitors are not shown in the online run screen in Performance Center. Furthermore, the following error is displayed in the output/messages window:

Monitor name: HP Simulation – Services. Cannot connect to <host-name>.
Reason: Cannot access HKEY_PERFORMANCE_DATA key on host myd-vm02858 with error
Access is denied.
(entry point: chkConnection).    [MsgId: MMSG-47281]
Check that your login user name appears as administrator on this machine.
Check that remote registry is available on this machine.
Check that you have entered the correct machine name.
Check that the machine exists and that it is online (use the ping utility for this operation).
Delete the machine and add it again. (entry point: CFactory::Initialize).  [MsgId: MMSG-47299]

The issue happens because the Windows resource monitor lacks permissions to access the remote server registries for the Service Virtualization counters.

There are two ways to fix the issue, both involving a single registry key edit that does not require a server reboot. The difference between both ways is the number of users that will eventually gain access to the new registry keys required for accessing performance counters on a server. Both ways require a registry change as Microsoft has not implemented a way to change this setting via a UI.