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3SL Web-based newsletter for September 2007 [Cradle 5.6]

Hints and Tips to Improve Cradle Performance

All parts of Cradle are designed to deliver the maximum performance to end users. This includes aspects such as:

  • Designing Cradle from the outset to support large numbers of simultaneous users
  • Equal responsiveness to large numbers of users by the CDS
  • Underlying design of the Cradle database
  • Gradual, not dramatic, degradation in performance with large data volumes
  • Optimisations in the Cradle software

The performance of a Cradle system will, however, degrade as a project database gets larger and larger and as the number of simultaneous users increases.

At 3SL, we are working to improve the performance of Cradle further and we believe that users will notice useful performance improvements in the next Cradle release, Cradle-5.7.

However, there are several things that you can do to get the best performance from your Cradle system. These are listed in the following sections:

Query Size

Most operations begin by running a query in the database to find items to work on. Either you explicitly run a query, or a query is run implicitly, for example when:

  • Opening a tree to explore a collection of items
  • Opening a node in the project phase hierarchy
  • Looking for items linked to a given item, either by expanding a tree node or by a cascade menu

In such cases, WorkBench searches the database for items that match the criteria in the query or are linked to the given item, or both.

The default block size for queries is 1,000 items, so queries will return blocks of no more than 1,000 items from the database, even if there are more items that could be returned. You get to the next and previous blocks of items by selecting the Next... and Previous... controls in list, tree or table views.

Reducing the block size reduces the time that a query takes to run. We recommend that you use the smallest block sizes that you find convenient to get the best performance when running queries.

Setting the query block size in WorkBench:

  1. Select File → Options and change to the Misc tab

  2. Change the value of the Max List Items: field to the desired value in the range 100 to 8,000, the default is 1,000 in the system startup files supplied by 3SL
  3. Select OK
Setting the query block size in Toolset
  1. Select Tools → Customise → UI Control… and select List Control…


  2. Change the value of the Size of item queries to PDB: field to the desired value in the range 100 to 8,000, the default is 1,000 in the system startup files supplied by 3SL
  3. Select OK
  4. In the UI Control Options dialogue, select Write… and select OK in the resulting dialogue
  5. Select OK to close the UI Control Options dialogue

Querying Frames

It takes about twice as long to run a query which includes searching the contents of one or more frames than a query which does not search frames’ contents.

We therefore recommend that searching the contents of frame(s) in queries should be used carefully, especially if the query is likely to be used frequently.

Default Views

Each query has a default view used to show the items that it finds, unless another view is specified, for example in a phase hierarchy node. If a default view is not specified, the last view used for that type of item will be used to show the query’s results.

In general, it is much quicker to display items in a view that does not use frames when compared to a view that does include frames.

Therefore, wherever possible:

Always define a default view, so you have control over the view that will be used

The default view for a query should not include any frames

The default view for a query should not include any linked items

Indicate Linked Items in Trees

When a list of items in WorkBench is shown as a tree, each item has a small + character next to it that indicates that the item has other items linked to it:

You can approximately double the speed with which such lists are shown by suppressing the display of the + characters. The operations in trees (for example double-clicking the item to expand the tree at that point), are still available irrespective of whether the + characters are shown, or not.

Disabling linked item tree markers in WorkBench

  1. Select File → Options and change to the Misc tab

  2. De-select the Indicate linked items in trees checkbox
  3. Select OK

Showing Suspect Items

All Cradle clients can highlight suspect items. An item is suspect if it is at the to end of a cross reference and the item at the from end of the cross reference has been modified more recently than it.

It takes approximately twice as long to generate a list of items, or a list of linked items, when Cradle has to test each item to see if it is suspect.

Therefore, we recommend that suspectness should only be enabled when needed and should be disabled as soon as it is no longer required.

Enabling display of suspect items in WorkBench

  1. Select File → Options and change to the Misc tab

  2. Select the Show Suspect Integrity combo box and choose Suspect or Suspect due to my changes
  3. Select OK

Enabling display of suspect items in Toolset

  1. Select Tools → Customise → UI Control…
    1. Change the setting of the SHOW SUSPECT INTEGRITY menu to be Suspect or Suspect due to my changes
    2. Select Write… and select OK in the resulting dialogue
    3. Select OK to close the UI Control Options dialogue

    Querying for Latest Items

    When searching the database, you can request only the latest instance of each item. An instance is a particular version and draft of an item. If Cradle’s Configuration Management System (CMS) is in use, several instances of an item can exist, for example:

    • Version 1 (no draft) of the item, superseded in an old baseline
    • Version 2 (no draft) of the item, superseded in an old baseline
    • Version 3 (no draft) of the item, in the latest baseline
    • Version 3 draft A of the item, the work-in-progress instance of the item

    With typical access rights, the first two of these instances (versions 1 and 2) would not be accessible, because they are superseded. So when you run a query with Owner set to ALL, then two instances would appear in the list, table or tree:

    • Version 3 (no draft) of the item, in the latest baseline
    • Version 3 draft A of the item, the work-in-progress instance of the item

    If you run a query with Owner set to LATEST, only one instance of the item will be found:

    • Version 3 draft A of the item, the work-in-progress instance of the item

    Therefore querying with LATEST finds the latest instance of an item, where latest means:

    • Higher version numbers supersede lower version numbers
    • A draft instance of an item supersedes a baselined (no draft) instance of the same version

    However, a query with Owner set to LATEST can take up to three times as long to run as a query with Owner set to ALL.

    Therefore, we recommend that queries using Owner set to LATEST should be considered carefully, especially if they will be used frequently.

    Accessing Link Details

    In WorkBench, when linked items in trees are selected to edit the attributes of the cross reference to them, right-clicking to display the pop-up menu to select Link Details can be time consuming. Before displaying this pop-up menu, WorkBench must assemble a list of all items that are linked to the selected item.

    If you simply want to view or edit the details of the cross reference to a selected item, then the quickest method to display these attributes is to select the item and then display the Link Details button in the top-right corner of the WorkBench UI:

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