Save as template

Stores all load test input parameters additionally inside an XML template. Later, this template can be used to rerun (repeat) the same load test.

Execute Test From

selects the Exec Agent or the Exec Agent Cluster from which the load test will be executed.

Apply Execution Plan

Optionally, an Execution Plan can be used to control the number of users during the load test. The dropdown list shows the Execution Plans' Titles, extracted from all formal valid Execution Plan files (*.exepl files), located in the current Project Navigator directory. Note that the titles of invalid Execution Plan files are not shown. If an Execution Plan is selected, then the following input parameters are disabled: Number of Concurrent Users, Load Test Duration, Max. Loops per User, and Startup Delay per User.

Number of Concurrent Users

The number of simulated, concurrent users.

Load Test Duration

The planned duration of the load test job. If this time has elapsed, all simulated users will complete their current loop (repetition of web surfing session) before the load test ends. Thus the load test often runs a little bit longer than the specified test duration.

Max. Loops per User

This limits the number of web surfing session repetitions (loops) per simulated user. The load test stops if the limit has been reached for each simulated user.

Pacing

Minimum Loop duration per User. Enabling this option sets a minimum time for all in the iteration executed page breaks and URL calls which must be elapsed before the next iteration starts.
If the iteration completes earlier than the pacing time, the user will be inactive until the pacing time has been reached.

Startup Delay per User

The delay time to start an additional concurrent user (startup ramp of load). Used only at the start of the load test during the creation of all concurrent users.

Max. Network Bandwidth per User

The network bandwidth limitation per simulated user for the downlink (speed of the network connection from the webserver to the web browser) and the uplink (speed of the network connection from the web browser to the webserver). By choosing a lower value than "unlimited," this option allows simulating web users with a slow network connection.

Request Timeout per URL

The timeout (in seconds) per single URL call. If this timeout expires, the URL call will be reported as failed (no response from the webserver). Depending on the corresponding URL's configured failure action, the simulated user will continue with the next URL in the same loop, or it will abort the current loop and then continue with the next loop.

Max. Error-Snapshots

Limits the maximum number of error snapshots taken during load test execution. The maximum memory used to store error snapshots can be configured (recommended - for cluster jobs: value overall cluster members). The maximum number of error snapshots per URL can be configured (not recommended for cluster jobs: value per Exec Agent).

Statistic Sampling Interval

statistic sampling interval during the load test in seconds (interval-based sampling). Used for time-based overall diagrams like, for example, the measured network throughput.

Additional Sampling Rate per Page Call

Captures the measured response time of a web page when a simulated user calls a web page (event-based sampling). Used to display the response time diagrams in real-time and in the Analyse Load Test Details menu. For endurance tests over several hours, it is strongly recommended that the sampling rate for web pages is set between 1% and 5%. For shorter tests, a 100% sampling rate is recommended.

Additional Sampling Rate per URL Call

captures the measured response time of a URL each time when a simulated user calls a URL (event-based sampling). Used to display the response time diagrams in real-time and in the Analyse Load Test Details menu.

In addition to capturing the URL calls' response time, further data can be captured using one of the Add options.

--- recommended: no additional data are captured

Performance Details per Call: additionally, the TCP/IP socket open time (network establish time), the request transmit time, the response header wait time, the response header receive time, and the response content receive time URL calls are captured.

TCP/IP Client Data: additionally the (load generator) TCP/IP client address, the TCP/IP client port, the network client-socket create date, the reuse count of the client-socket (keep-alive), and the SSL session ID (for encrypted connections only) are captured. This option also includes the option "Performance Details per Call."

Resp. Throughput Chart per Call: additionally, in-depth throughput data of the received HTTP response content are captured and displayed as a chart (stream diagram of response). This option also includes the option "Performance Details per Call."

Request Headers: additionally, the request headers of all URL calls are captured. This option also includes the option "Performance Details per Call."

Request Content: additionally, the request content data of all URL calls are captured. This option also includes the option "Performance Details per Call."

Request Headers & Content: additionally, the request headers and request content data (form data) of all URL calls are captured. This option also includes the option "Performance Details per Call."

Response Headers: additionally, the response headers of all URL calls are captured. This option also includes the option "Performance Details per Call."

Response Headers & Content: additionally, the response headers and the response content data of all URL calls are captured. This option also includes the option "Performance Details per Call" and "Resp. Throughput Chart per Call".

All - But w/o Response Content: additionally, the request headers, the request content data, and the response headers of all URL calls are captured. This option also includes the option "Performance Details per Call" and "Resp. Throughput Chart per Call".

All - Full URL Snapshots: additionally, all data of the URL calls are captured. This option also includes the option "Performance Details per Call" and "Resp. Throughput Chart per Call".

Debug Options

Choosing any debug option (other than "none") affects that additional information is written to the *.out file of the load test job. The following debug options can be configured:

none - recommended
Recommended default value. Note that error snapshots are still taken, and therefore special debug options are normally not necessary to analyze a measured error.

debug failed loops
Write the performed execution steps of all failed loops to the *.out file of the load test job.

debug loops
Write the performed execution steps of all loops to the *.out file of the load test job.

debug headers & loops
Write additionally debug information about all transmitted and received HTTP headers to the *.out file of the load test job.

debug content & loops
Write additionally debug information about all transmitted and received content data to the *.out file of the load test job (without binary content data like images).

debug cookies & loops
Write additionally debug information about all transmitted and received cookies to the *.out file of the load test job.

debug keep-alive & loops
Write additionally debug information about the behavior of re-used network connections to the *.out file of the load test job.

debug SSL handshake & loops
Write additionally debug information about the SSL protocol and the SSL handshake to the *.out file of the load test job.

Additional Options

Several additional options for executing the load test can be combined by adding a blank character between each of the options. The following additional options can be configured.

-multihomed
Initiates all Exec Agents to use multiple local IP addresses when executing a load test. This option allows simulating traffic from more than one IP address per Exec Agent. This option is only considered if the Exec Agent supports a multihomed network configuration (several IP addresses assigned to the same host). The first step to use this option is to configure the Windows or Unix operating system multiple IP addresses for the same host. The second step is to assign these IP addresses to the Exec Agent configuration. For the localhost, where the Web Admin GUI is running, the second step can be done by calling the Setup menu inside the Project Navigator (gear-wheel icon at the top navigation). For remote Exec Agents, you have to edit the file javaSetup.dat, located inside the ZebraTester installation directory - by modifying the entry value javaVirtualIpAddresses: enter all IP addresses of the host on the same line, separated by comma characters.
This option's effect is that each concurrent user uses its own client IP address during the load test. If fewer IP addresses are available than concurrent users are running, the IP addresses are averaged across the users.

-ipperloop
Using this option combined with the option -multihomed effects that an owned local IP address is used for each executed loop rather than for each simulated user.
This option is considered only if also the option -multihomed is used.

-tconnect <seconds>
Set a timeout in seconds to open a TCP/IP socket connection to the Web server. If the time is exceeded, the URL call is aborted and marked as failed. Note that the value must be greater than zero but should be less than "Request Timeout per URL."

-dnshosts <file-name>
Effects: The load test job uses an own DNS hosts file to resolve hostnames rather than the underlying operating system's hosts file.
Note that you have to ZIP the hosts file together with the compiled class of the script. To automate the ZIP, it's recommended to declare the hosts file as an external resource (w/o adding it to the CLASSPATH).

-dnstranslation <file-name>
Effects: The load test job uses a DNS translation file, a text file containing a translation between two DNS names. If the first DNS name in the file matches the DNS name passed to the resolver, then the second DNS name is used to resolve the IP address.
The first DNS name can also contain one or more wildcard characters ('*' = wildcard for multiple characters, ‘?' = wildcard for a single character). Lines or a part of a line can be commented on using the hash char '#.’

-dnssrv <IP-name-server-1>[,<IP-name-server-N>]
Effects that the load test job uses specific (own) DNS server(s) to resolve hostnames - rather than to use the DNS library of the underlying operating system.
When using this option, at least one IP address of a DNS server must be specified. Multiple DNS servers can be configured separated by commas. If a resolved DNS hostname contains multiple IP addresses, the stressed Web servers are called in a round-robin order (user 1 uses resolved IP Address no. 1, user 2 uses resolved IP Address no. 2, etc.).

-dnsenattl
Enable consideration of DNS TTL by using the received TTL-values from the DNS server(s).
This option cannot be used in combination with the option -dnsperloop.
Note: when using this option, the resolved IP addresses (and therefore the stressed Web servers) may alter inside the executed loop of a simulated user at any time - suddenly from one URL call to the next one.

-dnsfixttl <seconds>
Enable DNS TTL by using a fixed TTL-value of seconds for all DNS resolves. This option cannot be used in combination with the option.

-dnsperloop
Perform new DNS resolves for each executed loop. All resolves are stable within the same loop (no consideration of DNS TTL within a loop).
This option cannot be used in combination with the options -dnsenattl or -dnsfixttl.
Note: consider when using this option that the default or the configured DNS servers are stressed more than usual because each simulated user's executed loop will trigger one or more DNS queries.

-dnsstatistic
Effects that statistical data about DNS resolutions are measured and displayed in the load test result using a DNS stack on the load generators.
Note: there is no need to use this option if any other, more specific DNS option is enabled because all (other) DNS options also effect implicitly that statistical data about DNS resolutions are measured. If you use this option without any other DNS option, the (own) DNS stack on the load generators will communicate with the default configured DNS servers of the operating system - but without considering the "hosts" file.

-dnsdebug
Effects that debug information about the DNS cache and DNS resolves are written to the stdout file (*.out) of the load test job.

-enableIPv6 [<network-interface-name>]
Enable IPv6 support only for load test execution (IPv4 disabled). Optionally you also can provide the IPv6 network interface name of the load generators(s), like "eno," for example.

-enableIPv6v4 [<network-interface-name>]
Enable IPv6 and IPv4 support for load test execution (first will try with IPv6, if fails, will try with IPv4). Optionally you also can provide the IPv6 network interface name of the load generators(s), like "eno," for example.

-mtpu <number>
Allows configuring how many threads per simulated user are used to process URLs in parallel (simultaneously). Note: This value applies only to URLs that have been configured to be executed in parallel.

-nosdelayCluster
Effects for Cluster Jobs that the Startup Delay per User is applied per Exec Agent Job instead of applying it overall simulated users of the Cluster Job. Thus a faster ramp-up of load can be achieved.

-setuseragent "<text>"
Replaces the recorded value of the HTTP request header field User-Agent with a new value. The new value is applied for all executed URL calls.

-noECC
Disable elliptic curves (ECC).

-sslcache <seconds>
Alters the timeout of the user-related SSL cache. The default value is 300 seconds. A value of 0 (zero) affects that the SSL cache is disabled.

-sslrandom <type>
Set the type of random generator used for SSL handshakes. Possible options are "fast", "iaik" (default) or "java".

-sslcmode
Apply SSL/HTTPS compatibility workarounds for deficient SSL servers. You may try this option if you constantly get the error type "Network Connection aborted by Server" for all URL calls.

-nosni
Disable support for TLS server name indication (SNI).

-snicritical
Set the TLS SNI extension as critical (default: non-critical).

-tlssessiontickets
Set the TLS to use Session Tickets for session resuming (non-critical).

-iaikLast
Adds the IAIK security provider at the last position (instead of the default: IAIK at first position).
Note: Adding the IAIK security provider at the last position may have the side effect that weak or short cipher keys are used.

-tz <timezone>
Sets an alternatively time zone which is used by the script. The default time zone is equal to the selection made when installing ZebraTester, or - if modified subsequently - which has been set in the Personal Settings menu. Possible time zone values are described in chapter 6 of the Application Reference Manual.

-Xbootclasspath/a:<path>
Specify for the load test job a path of JAR archives and ZIP archives to append to the default bootstrap classpath.

-Xbootclasspath/p:<path>
Specify for the load test job a path of JAR archives and ZIP archives to prepend in front of the default bootstrap classpath.

-Xmx<megabytes>
Specify for the load test job the size of the Java memory in megabytes. Do not enter a space or a colon between the "-Xmx" and the value.
Note: this option can only be used if the corresponding Exec Agent(s) supports this option, meaning that the Exec Agent(s) is started with the option -enableJobOverrideJavaMemory.

-nostdoutlog
Disable to write any data to the stdout file of the load test job.

SSL: specifies which HTTPS/SSL protocol version should be used:

All: Automatic detection of the SSL protocol version. ZebraTester prefers the TLS 1.3 or TLS 1.2 protocol, but if the Web server does not support this, TLS 1.1, TLS 1.0, or SSL v3 is used. This is the normal behavior that is implemented in many Web browser products.

v3: Fixes the SSL protocol version to SSL v3.
TLS: Fixes the SSL protocol version to TLS 1.0.
TLS11: Fixes the SSL protocol version to TLS 1.1.
TLS12: Fixes the SSL protocol version to TLS 1.2.
TLS13: Fixes the SSL protocol version to TLS 1.3.

Browser Emulation

User-Agents and Caching

• User-Agent Selection: This option is used to create a custom user agent string or select a user agent from the available list.

• Browser Cache: This option emulates the cache setting of a real browser.

  • Check for newer versions of stored pages every time: when enabled, ZebraTester will check for later versions of the specified URL than those stored in the cache.

  • Cache URLs with HTML Content: when enabled, ZebraTester will cache the HTML resources as well. You can decrease the memory footprint of each VU by unchecking this option.

  • Simulate a new user each loop: when enabled, ZebraTester will create a new cache per loop.

Annotation

Enter a short comment about the test run, such as purpose, current web server configuration, and so on. This annotation will be displayed on the result diagrams.

<Exec Agent Name> or <Cluster Name>

The Exec Agent's name - or the Exec Agent Cluster's name - executes the load test job.

Job <number>

Unique job ID (unique per Exec Agent, or unique cluster job ID).

Real-Time Comment

If real-time comments are entered during test execution, these comments are later displayed inside all time-based diagrams of the load test result detail menu.

Job Parameter

The name of the load test program and the program arguments - test input parameter.

Web Transaction Rate

Open

The Web Transaction Rate Diagram shows the actual number of (successful) completed URL calls per second, counted overall simulated users. By clicking on this diagram, the Response Time Overview Diagrams are shown.

• Total Passed URL Calls - The total number of passed URL calls since the load test job was started.

• Total Failed URL Calls - The total number of failed URL calls since the load test job was started.

• HTTP Keep-Alive Efficiency (%) - The efficiency in percent about how often a network-connection to the webserver was successfully re-used, instead of creating a new network connection. This (floating) average value is calculated since the load test job was started.

• AV Web Trans. Rate (URL calls/sec) - The (floating) average number of (successful) completed URL calls per second, calculated since the load test job was started

Session Failures / Ignored Errors

Open

The Session Failures / Ignored Errors Diagram shows the actual number of non-fatal errors (yellow bars) and the number of fatal errors (red bars = failed sessions) counted over all simulated users.

• Total Passed Loops - The total number of passed loops (repetitions of web surfing sessions) since the load test was started.

• Total Failed Loops - The total number of failed loops (repetitions of web surfing sessions) since the load test was started.

• Σ User's Think Time per Loop (sec): The total user's think time in seconds for one loop per simulated user.

• Session Time per Loop (sec): The average session time for one loop per simulated user. This value is the sum of "the average response time of all URLs and all user's think times" per completed loop.

The Number of Users / Waiting Users Diagram shows the total number of currently simulated users (red bars) and the actual number of users who are waiting for a response from the webserver (purple bars). The users waiting for a response is a subset of the currently simulated users.

By clicking on this diagram, the Statistical Overview Diagrams are shown.

• Users Waiting For Response - the actual number of users waiting for a response from the web server, compared to ("of") the total number of currently simulated users.

• TCP Socket Connect Time (ms) - The time in milliseconds (per URL call) to open a new network connection to the webserver.

• AV Network Throughput (Mbit/s) - The total network traffic generated by this load test job, measured in megabits per second. This (floating) average value is calculated since the load test job was started.

• Total Transmitted Bytes - The total number of transmitted bytes, measured since the load test job was started.

Response Time (drop-down list)

Allows to select the period, from the current time back to the past, are shown in the diagrams within the response times.

Time Bars (drop-down list)

Allows selecting if the bars inside the diagrams are shown as average values or as max. values. Please note that there is only a difference between the max. values and the average values if multiple measured samples of the response time fall inside the same pixel (inside the same displayed bar):.

The tables at the right side of the diagrams contain the response times for all URLs of the web page. Also, these response times are either average values or max. values, depending on the selection in the Time Bars drop-down list. However, these values are calculated since the load test was started and always "accurately" measured, which means that they do not depend on the value chosen for the "Additional Sampling Rate per Page Call."

You can click on a URL response time to show the corresponding URL Response Time Diagram.

On the left side inside the diagram, the web page's average response time is shown as red-colored text, calculated since the load test was started. But depending on the selected period, this value may not be displayed in every case. On the right side inside the diagram, the last measured value is shown.

Response Time (drop-down list)

Allows to select the period, from the current time back to the past, are shown inside the diagram within the response times.

Time Bars (drop-down list)

Allows selecting if the bars inside the diagram are shown as average values or as max. values. Please note that there is only a difference between the max. values and the average values if multiple measured samples of the response time fall inside the same pixel (inside the same displayed bar).

Total Passed URL Calls

the total number of passed calls for this URL.

Total Failed URL Calls

the total number of failed calls for this URL.

Average Size (Req. + Resp.)

the average size of the transmitted + received data per URL call.

Max. Response Time

the maximum response time ever measured.

Min. Response Time

the minimum response time ever measured.

Av. TCP Socket Connect Time

the average time to open a new network connection to the webserver, measured for this URL. a blank /[---] instead of a value means that never a new network connection was opened for this URL because HTTP Keep-Alive (re-using of cached network connections) was always successful. The additional percentage value shown in brackets at the left-hand displays the percentage of how often a new network connection was opened to the web server, in comparison to how often this was not necessary. This percentage value is also called the reverse keep-alive efficiency.

Av. Request Transmit Time

the average time to transmit the HTTP request header + (optionally) the HTTP request content data (form data or file upload data) to the webserver, measured after the network connection was already established.

Av. Response Header Wait Time

the average time for waiting for the first byte of the web server response (-header), measured since the request has (completely) transmitted to the webserver.

Av. Response Header Receive Time

the average time for receiving the HTTP response header's remaining data, measured since the first byte of the response header was received.

Av. Response Content Receive Time

the average time for receiving the response content data, for example, HTML data or the data of a GIF image.

Average Response Time

the average response time for this URL. This value is calculated as \\.