8.5 leaks memory at 65 MB every hour

I’ve been building a new template where my Cubase machine has several VSTs in the rack. In the past, I’ve offloaded the majority of instruments to a VEP server machine. This time I loaded up about a third of my DAW machine’s RAM with VSTs as well.

When I leave that session open for over 24 hours, my DAW machine would hang and I would have to power down with the hardware button. I noticed that RAM usage of the machine was getting very close to peak (it’s an older machine with only 12 GB).

I created a Windows PerfMon data set to monitor the cubase8.5.exe process. I loaded the template and recorded Private Bytes, Working Set - Private, and Working Set. I let Cubase run for 16 hours, leaving the machine alone. The Working Set had increased by almost 1.1 GB. Other RAM metrics on the process went up proportionally.

I tried again with variations of the template loaded and saw similar results (rebooting between tests). When I removed all local VSTs and only had 6 VEP instances in the Rack, it sill showed RAM usage increasing by about 65 MB per hour.

All these tests were done with “MIDI Retrospective Record” DISABLED. (see https://www.steinberg.net/forums/viewtopic.php?f=229&t=70155&p=501911). I can go into more detail on monitoring a specific process in Windows for anyone who is interested. It’s not terribly hard to do.

Has this memory leak been fixed in Cubase 9? Rebooting the machine every day is not an option.

This appears to be caused by a plugin from SoundToys called “Tremolator” (http://www.soundtoys.com/product/tremolator/). I have a request into them to verify. If a third-party plugin is responsible, you can probably close this bug report. I will let you know what they have to say.