The purpose of the new Audio Performance Meter is to give you a more detailed feedback on the audio engine load situation and to allow for a quick diagnosis of audio engine issues. To achieve this, a new algorithm to separately measure the load for real-time and prefetch (ASIO-Guard) threads has been implemented.
The metering toolbar displays the current real-time, ASIO-Guard and peak loads. This not only offers a quick overview of the overall system load, but also provides a detailed indication of the source of the current system load.
The purpose of the distinction between real-time (average) and real-time (peak) is to identify issues which are caused by a high deviation between average and real-time. One example could be plug-ins which create a sporadic high peak load or which have an issue that directly affects the engine performance. Often, this needs to be investigated further.
Realtime
Show the average audio processing load of the latency critical processing path. This is the case for all live inputs or monitoring activated channels. It is always processed with the block size of the audio device settings.
ASIO-Guard
Shows the average audio processing load of the processing path, which can be processed in advance (prefetched). The block size depends on the ASIO-Guard settings found on the 'Audio System' page of the 'Studio Setup' dialog. If the audio interface is set to a small block size, it is a bigger block size than for real-time processing.
Peak
Shows the highest measured load (in the latency critical real-time processing path). If this meter peaks/clips, it will cause an audio dropout (see below).
Disk Cache
The metering of the current disk engine load is identical to the one used in previous releases.
Overload Indicator
The processing overload indicator at the right indicates dropouts if the processing load exceeds 100% or if the audio engine is restarted due to the internal detection of too high processing delays. For example, this might occur if the prefetch (ASIO-Guard) buffer runs empty due to a too high real-time load.
It is reset by clicking on it or whenever the engine is reinitialized due to audio device setting changes or when the reset button is pressed.
The overload indicator can also be reset with a key command now. You can find it under 'Audio Performance' → 'Reset Processing Overload Indicator' in the 'Key Commands...' settings in the 'Edit' menu.