Performance on Swabian Instruments

Transfer Rate Limits for Each Time Tagger Model

Tue, 20 Aug 2024 00:00:00 +0000

Time Tagger 20 utilizes a USB 2 interface, which limits the maximum transfer rate to about 9 MTags/s. Time Tagger Ultra and Time Tagger X instead utilize a USB 3 interface, allowing a maximum transfer rate of approximately 90 MTags/s; Time Tagger X additionally provides SFP+ and QSFP+ interfaces for even higher data rates, as described in later sections. Reaching high data rates depends on many variables, e.g. CPU performance, workload from other running processes, and power and performance settings; the figures above can only be achieved using a high-performance CPU with minimal workload from other applications running on the same computer.

CPU Performance Impact on Transfer Rate

Tue, 20 Aug 2024 00:00:00 +0000

We conducted tests to determine the maximum transfer rate achievable with different CPUs using either Time Tagger Ultra or Time Tagger X. The transfer rate for the Time Tagger 20 is limited by USB 2.0 and, therefore, does not depend on CPU performance.

Overflow Caused by Slow Data Processing

Tue, 20 Aug 2024 00:00:00 +0000

Buffer overflow can be caused not only by a data rate higher than the specified maximum transfer rate, but also by how quickly your software processes the incoming data, especially during computationally intensive measurements.

Each initialized measurement runs on its own thread, but only a few of our API measurements, such as HistogramLogBins, can utilize multiple cores. If a single measurement consumes excessive CPU time, the Time Tagger’s hardware buffer can fill up, leading to an overflow event and data loss.

Recommended USB Accessories

Tue, 20 Aug 2024 00:00:00 +0000

When setting up a Time Tagger, you may need to place it further from your PC than a standard USB cable allows, or share a single PC among multiple instruments. High-quality USB extenders, hubs, and docking stations can do this without reducing the data transfer rate from the Time Tagger to the PC — as long as you pick accessories that are up to the task.