On the
Workload Configuration dialog, on the
Pacing tab, you can perform the following actions:
- You can let
Silk Performer calculate the
Max. VUsers
- You can let
Silk Performer calculate the
Sessions Per Peak Hour
- You can let
Silk Performer calculate the
Goal Trans Per Second
- You can set your own specific
Goal Session Time by enabling pacing
Tip: You can copy and paste the values in the
Workload Configuration grids by using the keyboard shortcuts
Ctrl+C and
Ctrl+V or by right-clicking on a value and using the buttons in the context-menu.
Session Pacing
A
session is the group of transactions defined for a user in the
dcluser section. In the following sample, the session consists of 4 transactions. Note that begin and end transactions are not part
of the session. The
session time is the time it takes to execute the regular transactions including think times.
// Workload Section
dcluser
user
VirtUser
transactions
TInit : begin;
TLogin : 1;
TAddToCart : 2;
TCheckout : 1;
TEnd : end;
The
baseline session time shows how long it took to execute the session in the baseline test.
Session pacing causes
Silk Performer to add additional wait time, the so-called pacing wait time, at the end of a session before a new one is started. Session
pacing allows you to reach a specified fixed session length, the so-called
Goal Session Time.
Typically, you have already defined the number of virtual users in the
Adjust Workload workflow step. In this table, you can now see how many sessions the virtual users will manage to execute in one hour. This
is reflected by the
Sessions Per Peak Hour value. If you adjust this value,
Silk Performer will calculate how many virtual users you need to reach the number of sessions. On the other hand, if you adjust the number
of virtual users,
Silk Performer will recalculate the number of sessions the virtual users will manage to execute.
How the Sessions Per Peak Hour value is calculated
- Make sure you have set a baseline. See
Finding Baselines.
- Select to
Calculate virtual users required to reach a certain number of
sessions per hour.
- The
Baseline Session Time [s] column now contains the session time of each user type in the baseline.
- The
Sessions Per Peak Hour is calculated for each user type.
Here is an example of how
Silk Performer calculates the values: If the baseline test was executed in 100 seconds and you configured 10 virtual users, these 10 virtual
users will be able to execute about 360 sessions within one hour (10 x 3600 seconds / 100 seconds).
Session Per Peak Hour = (Virtual Users x 3600 seconds) / Baseline Session Time
How to set your own specific Goal Session Time
As outlined above,
Silk Performer uses the baseline session time to calculate the Sessions Per Peak Hour and the Max. VUsers. If you do not want to use the
given baseline session time but want the sessions of a user type to take a different time, you can set your own
Goal Session Time by configuring a pacing wait time.
How to configure Session pacing
- Select
sessions per hour to calculate the virtual users required to reach a certain number of sessions per hour.
- If you have set a baseline previously, the
Baseline Session Time [s] column now contains the session time value of each user type in the baseline. Your inputs in the subsequent steps will be
validated against the baseline.
- In the
Pacing column, click
... to open the
Configure pacing dialog.
- Click
Wait time insertion.
- Select the relative
Pacing wait time or the absolute
Goal Session Time and specify the value in the fields beneath the chart.
- Click
OK. Your
Goal Session Time displays in the table and the
Max. VUsers value is adjusted. The
Bandwidth value updates if a baseline has been set.
How to configure Think Time adaption
- Select
sessions per hour to calculate the virtual users required to reach a certain number of sessions per hour.
- If you have set a baseline previously, the
Baseline Session Time [s] column now contains the session time value of each user type in the baseline. Your inputs in the subsequent steps will be
validated against the baseline.
- In the
Pacing column, click
... to open the
Configure pacing dialog.
- Click
Think time adaptation.
- Select
Static or
Dynamic:
- Static: To reach the goal session time, the think times in the script are multiplied with a constant, static factor.
- Dynamic: To reach the goal session time, the think times in the script are multiplied with a dynamic factor that is recalculated
after each executed session.
- Define your
Goal Session Time and click
OK. Your
Goal Session Time displays in the table and the
Max. VUsers value is adjusted. The
Bandwidth updates if a baseline has been set.
Transaction Pacing
While
Session Pacing is adding pacing wait time at the end of the session,
Transaction Pacing is adding pacing wait time at the end of each individual transaction.
How to get the Goal Transactions Per Second calculation
- Select
transactions per second to calculate the virtual users required to reach a certain number of transactions per second.
- If you have set a baseline previously, the
Avg Transaction Time [s] column now contains the average transaction time value of each user type in the baseline.
- The
Goal Trans Per Second column is calculated for each user type row.
How to set your own specific Goal Transactions Per Second
- Select
transactions per second to calculate the virtual users required to reach a certain number of transactions per second.
- If you have set a baseline previously, the
Avg Transaction Time [s] column now contains the transaction time value of each user type in the baseline.
- In the
Pacing column, click
... to open the
Configure pacing dialog.
- Click
Wait time insertion.
- Select the relative
Pacing wait time or the absolute
Avg Goal Trans Time and specify the value in the fields beneath the chart.
- Click
OK. Your
Goal Session Time displays in the table and the
Max. VUsers value is adjusted. The
Bandwidth updates if a baseline has been set.