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Flow Properties

Flow properties control the InTime optimization flow. The following sections highlights the key properties. Refer to the Tcl Reference for the full list of properties. Not every property applies to all flows, for example, properties for Remote run targets are not applicable for Local.

Using Tcl

When using InTime in Tcl command line mode, you can change flow properties via the flow series of commands. For example:

# Set the value of a property:
flow set run_target local
# Get the value of a property:
set run_target_value [flow get run_target]
# Show current flow configuration:
flow properties

General Properties

Before clicking the "Optimize" button, please specify the required build resource parameters, most importantly, the number of compilations, the number of rounds to run, and finally the number of servers or builds in parallel. These properties control the most important aspects of the flow.

  • Run Target (run_target): Specifies where a job is compiled. For details on the different run targets, see run_targets. Default: depends on the available license. When no license is registered the default is plunify_cloud, otherwise the default is local.

    Value Description
    Local (local) Run strategies on a single, standalone machine where InTime is also being run.
    Private Cloud (private_cloud) Run strategies in your internal server farm using the InTime run-targets-private-cloud.
    Plunify Cloud (plunify_cloud) Run strategies on a Plunify-managed cloud using the run-targets-plunify-cloud.


    When selecting the Private Cloud run target, please make sure your Private Cloud is properly configured as described in the InTime Configuration Guide.

  • Runs Per Round (runs_per_round): The number of strategies to compile per iteration. You can set this number to 0 in which case InTime will compile only your original project (the "parent revision"). This lets you manage and build up a comprehensive history of all the builds performed on a design, even if you are not generating strategies via InTime. Note that InTime learns more effectively with a higher number of runs per round. Valid Range: 0-1000.

  • Rounds (rounds): The number of iterations (each iteration consists of one or more strategies). Similar to Runs Per Round, the more rounds you run, the more effective InTime's learning capabilities become. Valid Range: 1-100. The total number of runs will be runs_per_round * rounds.

  • Concurrent Runs (concurrent_runs): The number of strategies to compile in parallel. The context of concurrency and the default value depends on the selected run target:

    Value Description
    Local The number of parallel builds on a single machine. Default: 1.
    Private Cloud The number of builds across multiple machines to assign to this job. Default: The concurrent run limit of the private cloud license.
    Plunify Cloud The number of Plunify Cloud servers to assign to this job. Default: 100.

Properties related to the goals of the InTime flow.

  • Recipe Goal (goal): Design goal to aim for. Default: speed.

    Value Description
    Speed - TNS (speed_tns) Achieve timing closure by attempting to minimize the design's Total Negative Slack (TNS) (also referred to as Timing Score by some FPGA software).
    Area (area) Reduce device utilization.
  • Goal Based Target (goal_based_target): The target result to aim for. Default: 0. The value represents the following, depending on the selected goal:

    Value Description
    Speed - TNS (speed_tns) The TNS to aim for.
    Area (area) The device utilization percentage to aim for.
  • Stop When Goal Met (control_stop_when_goal_met): When true, stop as soon as one of the generated strategies meets the design goal. Otherwise, continue until the recipe completes. Default: true.

Parent Revision Properties

Properties related to the "parent revision" of each round within a job. Each round has a parent revision which is the point of reference for generating strategies and determining result improvements for recipes. The parent revision of the very first round is called the the base or root revision (the root of a tree of results). while parent revisions of subsequent rounds are called custom parent revisions. Finally, when opening a project, InTime detects the active revision / run in the project and keeps track of it.

  • Initial Compilation (initial_compilation): The Run Target to use when InTime builds the root revision of the design. Default: local.

    Value Description
    Local (local) Build using the machine on which InTime is running.
    Skip (skip) If the root revision's results are not required for comparison, choose this option to reduce runtime. Some recipes, such the seed exploration ones, automatically skip building the root revision.
  • Name (parent_revision_name): The topmost revision in a round of builds / strategoes. Initially, this is the FPGA project's active revision, but subsequently, the user can change it to any revision in the project or in the InTime build history. Default: The active revision / run of the FPGA project.

  • Job Id (parent_revision_job_id): When 0, InTime looks up the parent_revision_name from the project and fails if it does not exist. On the other hand, when not 0, InTime attempts to find a job with the ID specified in the project's InTime build history. If found, InTime looks for a revision matching parent_revision_name within that job, and uses that strategy along with its results as the parent revision for the next round. Default: 0.

The InTime GUI makes it easy to set any result in a project's history as the custom parent revision of the next iteration by right-clicking on the result in the project build history, and selecting "Set As Parent Revision". See recipes_further_exploration for more information on setting a custom parent revision.

Flow Control Properties

Properties which control flow decisions and outcomes, and may not be available depending on the FPGA tool.

  • Allow Eval IP (control_allow_eval_ip): Trial IP cores usually have different timing performance compared to licensed IP cores, and are typically not used for production builds. Enable this property to permit the use of trial IP cores. Default: false.

  • Create Bitstreams (control_create_bitstreams): Indicates if programming files should be generated for each strategy. Normally it does not make sense to do so since programming file generation adds to runtime. Default: false. For some toolchains, a side-effect of setting this to false is that power estimates will not be done.

  • Force Continue (control_force_continue_when_no_results): Normally InTime does not proceed to the next round of strategies if there are no no results (failed or stopped strategies) in the current round. Toggling this property compels InTime to still proceed in such a situation. Default: false.

  • Ignore DRC Errors (control_ignore_drc_errors): Design Rule Checks (DRC) can be deemed excessive at time. Enable this property to disregard DRC failures and continue compiling the design. Default: false.

  • Regnerate IP Targets (control_regen_ip_targets): Certain IP cores can be compiled independently and saved as netlists. InTime archives your FPGA project and builds a copy for every InTime strategy. To reduce runtime, InTime assumes that every required IP netlist is archived properly. If you are encountering synthesis errors about missing modules or netlists, enable this property to re-compile all IP cores. Default: false.

  • Reuse Routed Netlist (control_reuse_routed_netlist): Indicates if the post-route parent revision circuit should be used in order to reduce build runtimes. Default: false.

  • Reuse Synthesis Results (control_reuse_synthesis_results): Indicates if synthesis results should be reused in order to decrease build runtimes. When enabled, only place & routing exploration is done, reusing synthesis results from the parent revision. Default: false. The following restrictions apply:

    - Only supported for `educated`, `oneshot` strategy algorithms.
    - Only supported when `initial_compilation` is `local`.
    - Not available for the `plunify_cloud` run target.
  • Stop If Post-Place Timing Is Bad (control_stop_when_post_place_timing_bad): Post-placement timing can be a good indicator of final timing, so you can reduce your optimization turnaround time by enabling this option to terminate builds based on timing results just after placement. Default: false.

    Value Description
    Post-Place TNS Limit(ns) (post_place_tns_limit) Total Negative Slack value below which InTime will terminate any build. Default: -1000
    Post-Place Worst Setup Slack Limit(ns): (post_place_wns_limit) Worst Setup Slack value below which InTime will terminate any build. Default: -0.9
    Post-Place Worst Hold Slack Limit(ns): (post_place_whs_limit) Worst Hold Slack value below which InTime will terminate any build. Default: -0.9

    When enabled, any of the Limit values meeting the threshold value results in InTime terminating the build.

    Please refer to "How to reduce run time with post placement estimates" for more information on how to use these options.

Properties related to the generation of strategies.

  • Algorithm (strategy_algorithm): The approach to take. Default: Controlled by the recipe.

    Value Description
    Educated (educated) This approach uses existing knowledge in the InTime database to generate strategies which are optimized for the design. The training_data_filter property controls which correlations to apply when making decisions during the generation of new strategies.
    Custom (custom) Uses strategies that you create. For information on implementing custom strategy generation algorithms please refer to advanced-concepts-custom-strategy-algorithms.
    Oneshot (oneshot) This approach uses the project's whitelist and blacklist as guides to generate strategies containing all possible combinations of the specified tool settings. The seed exploration recipes are examples of how this approach works.
  • Auto Adjust Clock Margin Value (auto_clock_margin_adjustment): Applicable only to the Clock Margin Exploration recipe, this property makes InTime generate clock margin values for strategies. Default: True.

  • Auto-Optimize Max Runtime (auto_max_runtime): Adjust Maximum Runtime automatically based on the runtimes of the previous job. Default: False.

  • Auto-Sync Results (auto_sync_results): Match your project path and name to existing results in your InTime database, and automatically link matching results to your project. Default: True.

  • Clock Margin Initial Value (strategy_clock_initial_value): Applicable only to the Clock Margin Exploration recipe, set this property (in ns) as the starting clock margin quantity to explore. Default: 0.05

  • Clock Margin Increment (strategy_clock_increment_value): Applicable only to the Clock Margin Exploration recipe, set this property (in ns) as the clock margin quantity to increase for each strategy. Default: 0.05.

  • Custom Strategy (strategy_custom): The name of the strategy to use when strategy_algorithm is set to custom.

  • Implementation Name to Export (strategy_export_impl_name): Allows you to specify the implementation run name when you output an InTime strategy to your project.

  • Max Runtime (strategy_max_runtime): The maximum allowed runtime (in hours) per strategy. Default: 12, Valid Range: 0-48.

  • Max Runtime Unit (strategy_time_unit): Choose how InTime monitors build runtime - in Seconds, Minutes or Hours in order to terminate builds that exceed a certain runtime. Default: Hours

  • Settings Scope (strategy_settings_scope): How strategy settings are applied to the parent revision. Default: additive.

    Value Description
    Additive (additive) Add settings defined for the strategy on top of existing settings of the parent revision. If a setting exists both in the strategy as well as the parent revision, the value defined for the strategy will be used.
    Restrictive (restrictive) Use only settings defined for the strategy, omitting all existing settings of the parent revision.
  • Strategy Prefix (strategy_prefix): Each generated strategy is assigned a unique name within a job's context. This property allows control over the name used to derive strategy names. For example, if the strategy prefix is calibrate, strategy names will typically be calibrate_1, calibrate_2 etc. Informative prefixes give a better idea of what a recipe does (refer to the recipes in InTime).

  • Strategy Retries If Fail (strategy_retry_count): Due to unexpected events like machine crashes or network outages, your InTime builds may fail. Specify the maximum number of attempts to re-build a strategy. Applies only to Private Cloud builds. Default: 3.

  • Strategy Reuse Multiplier (strategy_reuse_multiplier): Influences how many past results are re-used when generating Hot Start strategies. This value ranges from 0.0 (no reuse) to 10.0 (as much reuse as possible). Default: 0.5.

  • Strategy Start Interval (strategy_delay_interval): In a Private Cloud environment, to load balance, you may not want all InTime builds to start simultaneously. Specify the number of seconds between the start of each strategy using this property. Default: 5 seconds.

  • Strategy Use Entire Results History (strategy_use_all_training_data): Controls the range of past results that Auto Pilot evaluates when deciding the next recipe. If true, Auto Pilot considers all the results up to the current point. If false, Auto Pilot considers only results from the latest job. Default: true.

  • Synthesis Name to Export (strategy_export_synth_name): Allows you to specify the synthesis run name when you output an InTime strategy to your project.

Cleaning Properties

Properties which control how InTime does housekeeping for files created during its flow.

The following items can be cleaned up per strategy:

  • Generated Files (generated_files): Files generated while creating, running and analyzing strategies. These include all files generated by the vendor tool as well as additional files created by InTime during result analysis. InTime puts all generated files in the <project_dir>/<job_id> directory. When the cleaning properties are not set to clean the generated files, the user can manually remove files. Note: InTime keeps specific files for in order to learn from the results. Those files are not removed even if you set this property.
  • Project References (project_references): Changes made to the project that are related to InTime strategies, including new project revisions etc.

The files to clean are set per strategy outcome. The following outcomes can be configured:

  • Met Goal (met_goal): Strategies which are built successfully and which meet the design goal.
  • Success (success): Strategies which are built successfully but which do not meet the design goal.
  • Stopped (stopped): Strategies which are stopped, either by the user or due to another strategy meeting the design goal (see control_stop_when_goal_met for more information).
  • Failed (failed): Strategies which failed.

The Generated Files cleaning properties are controlled either through the flow properties in the InTime GUI or through the Tcl command line interface. The Project References cleaning properties are only controlled through the Tcl command line interface. For an overview of the current clean configuration, use the flow get clean command:

plunify> flow get clean
Clean operations per strategy outcome:

-> clean generated_files = false
-> clean project_references = false
-> clean generated_files = true
-> clean project_references = true
-> clean generated_files = true
-> clean project_references = true
-> clean generated_files = true
-> clean project_references = true


The above configuration is the default configuration. To restore this default configuration, use flow set clean restore_defaults.

To change the default configuration, use the following command and one of the specified sub-commands:

flow set clean <all,generated_files,project_references> <run_state> <true,false>

For example:

# To keep all generated files:
flow set clean generated_files all false

# To keep all generated files only for builds which fail or meet the design goal:
flow set clean generated_files failed true
flow set clean generated_files met_goal true

# To clean everything:
flow set clean all all true
  • Keep DCPs (max_dcp_keep): Design Checkpoint or netlist files preserve intermediate compilation information. Some are saved so that they can serve as custom parent revisions for subsequent jobs. In order to conserver diskspace, you can set the number of Design Checkpoints to keep on hand. InTime prioritizes these netlists by order of Total Negative Slack, Worst Slack and then Area (logic utilization). Default: 999.

Training Data Filter Properties

Training data filter properties determine which build results are used as training data for InTime's machine learning algorithms when generating strategies. Default: Design&Device&ToolchainVersion.

  • Design: Only apply previous learning outcomes linked to the open project's design.

  • ToolchainVersion: Only apply previous learning outcomes linked to the current vendor toolchain version.

  • DeviceFamily: Only apply previous learning outcomes linked to the device family of the open project's design. For example: Cyclone II, Stratix V.

  • Device: Only apply previous learning outcomes linked to the device of the open project's design. For example: EP2C5F256C6.

  • DevicePackage: Only apply previous learning outcomes linked to the device package of the open project's design. For example: FBGA, TQFP.

  • DeviceSpeed: Only apply previous learning outcomes linked to the device speed grade of the open project's design. For example: 6, 7.

  • Jobs: Only apply previous learning outcomes linked to the specified jobs across all designs for which results are stored in your InTime runs database. Jobs can be specified using the following syntax:

    • =1,5,7: Specify individual jobs as a comma separated list preceded with =.
    • !=1,5,7: Exclude individual jobs by placing a ! in front of the job number, for example: !=1,5,7
    • >5: Specify job ranges. Supported operators include: < <= > <=.

The educated adjustment properties can be set in the Tcl console via the training_data_filter property. For example: :

flow set training_data_filter Design&Device&Jobs=5,6
flow set training_data_filter Design&Device&Jobs>=5
flow set training_data_filter Design&Device&Jobs!=5,6