Accelerating OS Compilation by Disabling Picture Tree and Block Icon Generation in PCS 7

In SIMATIC PCS 7 V8.1 and higher, OS compilation on large multi-server projects can take over 45 minutes because the compiler scans and updates every graphic picture to verify block icons. To drastically reduce compilation time to under 2 minutes for routine logic changes, uncheck the 'Picture Tree' option in the 'Select the data you want to compile' step of the OS Compilation wizard. Disabling Picture Tree skips the graphic picture sweep while still compiling all updated tags, alarm messages, and communication descriptors.

Root Cause Analysis of Extended OS Compilation Times on Large Projects

In large-scale SIMATIC PCS 7 facilities (comprising multiple OS Server pairs, dozens of OS Clients, and thousands of Process Objects), the Compile OS process can become a severe engineering bottleneck, frequently taking between 30 and 60 minutes to complete.

When an engineer analyzes the compilation progress window, the vast majority of execution time is spent on the phase:
Exporting and updating graphics: Opening, scanning, and saving PDL pictures...

This delay is caused by the Picture Tree Manager and Block Icon Sweep:
1. For every technological block in the Plant Hierarchy that has block icon generation enabled, the compiler opens the assigned process picture (.pdl).
2. It evaluates every existing block icon, checks attributes against @PCS7TypicalsAPL.pdl, modifies tag connections, and writes the updated graphic back to disk.
3. In projects with hundreds of process pictures, the repeated file system read/write cycles and graphics engine rendering create immense disk I/O and CPU overhead.

During daily software commissioning, 95% of engineering modifications involve only controller logic tuning, interlock modifications, or alarm threshold adjustments in CFC—tasks that require updating Tags and Messages, but do not alter the visual placement of block icons.

OS Compilation Options and Impact on Runtime Assets Matrix

Understand how the options in the OS Compilation wizard affect compilation time and runtime deliverables:

Compilation Wizard OptionDeliverables Generated / UpdatedTypical Execution Time ImpactWhen to EnableWhen to DisableTags and MessagesTag Management variables, Alarm Logging messages, Archive descriptorsFast (1 to 3 minutes)Always enabled for logic changesNever disable during program updatesPicture TreeScans all .pdl files; creates and updates block icons; builds hierarchyVery Heavy (20 to 45 minutes)When new blocks or new process screens are addedDisable for routine CFC logic tuningSFC VisualizationGenerates SFC runtime status tags and communication instancesModerate (2 to 5 minutes)When adding or updating SFC Charts/TypesDisable if project contains no SFCsWith Interconnected Partner (SFC)Evaluates cross-chart SFC interconnections and interlocking linksHeavy (5 to 15 minutes)When altering complex multi-chart SFC logicDisable for standard chart modifications

Productivity recommendation: Disabling Picture Tree during commissioning iterations recovers hours of engineering time daily.

Disabling Picture Tree and SFC Options in the OS Compile Wizard

Follow this procedure to execute rapid delta compilations:

Launch the OS Compilation Wizard:
* In SIMATIC Manager, select the Operator Station, right-click, and select Compile.
* Click Next through the introductory screens until reaching:
- Select the network connections. Verify Named Connections. Click Next.
Configure Data Scope Selection:
* In the dialog Select the data you want to compile:
- Keep Checked: Tags and messages.
- UNCHECK: Picture Tree.
- UNCHECK: With interconnected partner (SFC option) (if SFC cross-links are unchanged).
- Keep Checked: SFC Visualization (only if SFC state tags need refreshing).
Select Compilation Scope:
* Select Scope: Changes only.
* Click Compile.
Execution Performance:
* The compiler bypasses the graphics engine entirely, generating all WinCC tags, structure tags, and alarm messages in under 2 minutes.

Best Practices for Staged and Delta OS Compilations

Adopt a staged compilation workflow during plant commissioning:
1. Daily Development Phase (CFC Logic & Alarms): Compile with Tags and messages enabled and Picture Tree disabled. Download changes to OS servers instantly.
2. Graphics Staging Phase (Adding New Equipment): When new valves, motors, or measurements are introduced into CFC charts that require new block icons on screen, run a single coordinated compilation with Picture Tree checked.
3. Pre-Commissioning Baseline Phase: Prior to factory acceptance testing (FAT) or site commissioning, execute a full baseline compilation: Entire OS with memory reset, with all options checked to ensure 100% database consistency.

Verification

Verify rapid compilation results:
1. Note the compilation duration: Confirm that the process completes in under 2 minutes instead of 40+ minutes.
2. Inspect the compilation log: Confirm that tags and messages were compiled successfully with zero errors.
3. Open WinCC Runtime: Confirm that modified alarm thresholds and new CFC variables update cleanly on existing faceplates and trends.

Limitations and Operational Precautions

If you place a new technological block (e.g., a new motor MotL) in a CFC chart and compile with 'Picture Tree' unchecked, the WinCC tags will exist, but no block icon will be generated in the process screen. You must compile with 'Picture Tree' checked at least once to create the icon.
Disabling 'Picture Tree' does not update picture hierarchy navigation buttons in @Overview1.pdl if screens were renamed or rearranged in the Plant Hierarchy.
Never abort an OS compilation in progress; interrupting compilation can leave the WinCC CS database in an inconsistent state.

Engineer FAQ

Where was the 'Create/update block icons' option located in older PCS 7 versions?

In PCS 7 V6 and V7, this was an explicit checkbox labeled 'Create/update block icons' within the compilation wizard. In PCS 7 V8 and V9, this function is tied directly to the 'Picture Tree' selection.

Does compiling without Picture Tree affect WinCC Alarm Logging?

No. Alarm Logging messages and text libraries are compiled under the 'Tags and messages' option, completely independent of the Picture Tree.

Can I generate block icons for a single specific picture instead of all pictures?

Yes. In Graphics Designer, open the target picture and select Tools > Create/Update Block Icons. This runs the sweep exclusively on the currently open screen.