(Ran both DPC tools separately and did the same steps to recreate the pops and cracks). While as latencymon is only reporting about 20. But the moment I maximize Reason or Reaper the audio starts going crazy and the DPC checker is showing around 1000. DPC checker is saying its at about 15 and the audio is clear and I can play my midi keys with pretty much no issue.
I did however notice in both audio cracks/pops and the dpc checker spiking when graphic demanding things are taking place.įor instance, I'll launch this particular project and in the dpc checker it'll jump to 1000 until I minimize all of the Windows until I'm just staring at the desktop. I am using both of those tools as mentioned for the DPC checking. As in this song I have primarily used instruments in Reason and none in Reaper yet. Hmm okay I will run the project in Reason only and see what difference that makes. Because, as I explained before, its processing isn't possible to spread over multiple cores, this basically means, you have 8 core CPU, so its maximum in aggregate numbers fashion is 12,5%. If this figure is reaching 100%, you have problem. This is that important, previously mentioned thread, which communicates with ASIO driver. In Reaper, you have also good Performance Meter, which can optionally show something called RT CPU performance (enable it via right click at Performance Meter window).
So I would recommend to do your tests either just with Reason directly to ASIO driver or with Reaper directly to ASIO driver, with possible plugin or instrument processing directly there. This can also negatively affect latency performance. interprocess communication (IPC) also takes some time. Similarly, you've mentioned Rewire, which really means, main DAW application launch another separate process, whose threading is out of its control and directly depends on process output. so if you put 10 heavy plugins there, you can have low overall CPU utilization, but it will be dropping, because each plugin processing directly depends on output from previous one. Load from some processing tasks isn't possible to easily spread to multiple cores from DAW, like sequential processing at master track for example. If this one is overloaded or its processing is basically "postponed" due to wait for delivery of samples from another overloaded DAW thread, then dropout will also occurs. What is important, is good performance of main audio processing thread, which is transferring data between DAW and ASIO driver.
Overal CPU usage from all CPU cores isn't really much informative about that and low aggregated value doesn't mean, you're fine. Unfortunately it isn't so easy with multi-threading and multi-processing. ASIO performance and DPC is fine, but there is problem with distribution of particular load by DAW.
Get Windows Performance Toolkit and install just analyzer from setup options. Sometimes Microsoft Windows Performance Analyzer is best for getting proper DPC figures and has nice feature for graphical display of latency over time of measurement, which is super handy for finding of correlation between peaks at different drivers. figures is lower and there isn't problem in DAW. LatencyMon by Resplendence isn't 100% sometimes, but this is usually other way around - its reported DPC latencies are reported as problematic, but in reality sum of lat. Thesycon Latency Checker doesn't work at newer Windows than 7 and reports incorrect values.