Welcome to the new and improved ROSS website. Over the next few months this site will become the go-to place to learn more about ROSS.

Currently, the best resources for information are the wiki articles. Slowly, these articles will be updated and rewritten here as blog posts.

If you are currently developing a ROSS model and would like to request a new feature, please create an Issue on Github.

Latest Posts

  • Optimistic Parameters

    There are several different parameters that are available for tuning optimistic parallel mode in ROSS. Optimistic mode can be performed in two ways, the difference between the two ways is how the frequency of GVT computation is determined. The traditional way, --sync=3, uses the number of events to determine how frequently to perform GVT. This way means GVT will be performed after every batch x GVT-interval number of events (these parameters are explained in more detail below). The other method is similar, but GVT is performed after some amount of real time has passed (see Optimistic Realtime Scheduler for more details).

  • Instrumentation Overview

    There are several different modes of instrumentation have been added to ROSS that can be used to collect data on the simulation engine and/or the model being simulated:

  • Real Time Sampling

    This collects data at real time intervals specified by the user. The runtime option --rt-interval=n sets the sampling interval, where n is the number of milliseconds between sampling points. The default is set to 1000 ms.

  • GVT-based Sampling

    This collects data immediately after each GVT. By default, the data is collected on a PE basis, but some metrics can be changed to tracking on a KP or LP basis (depending on the metric).

  • Virtual Time Sampling

    In order to support virtual time sampling in ROSS, specialized LPs called Analysis LPs were added to the ROSS core. These LPs are hidden from the model, so they will not affect any LP to PE/KP mappings.