Latency / ASIO blocksize

The plugin supports low latency convolution and, in general, has a latency of one ASIO blocksize. However, there are some restrictions:

The used latency is always a power-of-two and is limited between 64 and 4096 samples. To sum this up, the latency is always one of these values: 64, 128, 256, 512, 1024, 2048, 4096

The performance on the CPU is near zero if the ASIO blocksize matches one of the values listed above. Other values will lead to a slightly increased CPU usage because there are times where the CPU has to wait for the GPU to complete computation, resulting in a blocking operation inside the call that is made by the host software.

GPU Performance Display

The GPU Usage meter displays a value in percent that displays the GPU consumption. This value represents the time that the whole computation process needed (transfer audio to GPU, compute, transfer audio back to CPU) divided by the length of the currently processed block in seconds.

For example, a block of 1024 samples at a samplerate of 44100 samples/sec has a length of 23ms. If the whole computation process needs 4ms of time, the GPU usage meter would display a usage of 17%

Transfer between GPU and CPU

As the transfer between GPU and CPU includes some overhead, the GPU usage display will raise if the blocksize is lowered. A higher blocksize is therefore recommended if affordable and allows more instances to be used.