Cpu Load > 70% = Crackles

whenever renoise signalizes a CPU load which is greater than ~70%, i get pops, crackles and other unpleasent noises plus slowdowns.
ever since i’m using renoise i was wondering why that already occurs at 70%, when there still should be some cpu reserves left.
anybody experiences the same and/or knows if that is normal?

I experience this aswell,
what I think is that this is due to a CPU/graphic overload.

seems that when CPU meter reaches 70%, my graphics card is already too slow to cope with CPU load

you should try to use a bigger buffersize. if I use 20ms I also get pops at 60-70%, when I use 150 or more, I rarely get something, even at 98%.

I think its because the cpu-load you see is only an average, real cpu-load might be wobbling around between 20% and 150%, so those 150% peaks give you these cracks. when using a bigger buffersize, renoise can smooth these peaks out, meaning, if it gets behind because of 150% it can catch up again if the cpu is only 20%.

I hope you understand what I mean.

it seems like you’re not talking about buffersize but about latency.
and i tried every possible combination of latency (everything possible ranging from ~20 - 180ms), buffersize (everything from 64-1024) and i even tried all these different settings with the two available audio interfaces (directsound & asio), but no avail…
whenever a song reaches ~70% i will get slowdowns and crackles.

I meant latency, sorry.

Oh, and too bad it does not work for you, it really did wonders here …
I have a song in progress which crawls about 90% when it goes to the really busy parts, and with a latency of 20 or 30 it just skips all the time … with 150 it runs smoothly enough to be edited. Anyway, I am just waiting for my new PC now, because I wanted to add some more things.

hehe… i was also thinking about a hardware upgrade because of renoise :P
what are the specs of your old & incoming machine?
and it really troubles me that my pc’s potential peaks at around 70% cpu load whereas yours still has some reserves left at that point… must be some reason for that… hmm


I experience the same at about 50-60% on a P4 2.26Ghz with 1.5Gb of ram. :(

But don’t be fooled by this number… when Renoise says 50-60%, I see 95-99% in Windows task manager… So the computer is REALLY working full speed… (otherwise there might be some bad coded parts in Renoise <_< … but I don’t think so, this happens in other audio software too)

In my opinion there should be CPU usage monitoring for each instrument/VST. There are a lot of really CPU hungry plugins out there (for example reverbs). Sometimes I use a VST reverb for subtle effect on sound, but that eats maybe 20-30% of the CPU! I didn’t knew it until recently (while using it with another soft), and now I turn it on almost only for rendering…

Keith303, I guess diffences in % depend on how Renoise is used. For songs with few megabites of samples and few native effects, I already got up to 80-90 without no problem.

But most of the time I use VSTi (sampled base ones, such as The Grand, Halion String Edition and Virtual Guitarist, althogether representing about 9GB of samples) and I got the problem around 50% then…

My experience is: if you use sample based VSTis then put LOTS of ram in your computer. I had songs that I could not hear “live” that I could hear again after a ram upgrade!

If you use mostly SoftSynths (other than samplers) and many effects, then CPU is more important…

well, i’m also talking about songs with a lot or even VSTi-only here.
without VSTi and just FX and samples, i’ve fortunately never managed to reach those 70 percent - but of course that’s also easily possible if the amount of FX you use reaches other dimensions…
guess i’ll most probably upgrade my P4 1.6@2.7Ghz, 512MB PC333, i845E to something more powerful soon… i’m just waiting for the next price drop for DDR RAM, which is rather expensive at the moment.
i’d definately like to see one of those canterwood babies equipped with a 800mhz FSB P4 in my case. drool :rolleyes:

remember that you can tweak your systems to edge out more juice! try reading the manuals that came with your pc. or surf for new software updates. they help quite a bit.

breakthru >> u’ve got 9GB of samples to play around each time, so maybe you gota arrange your samples properly, since they can’t all fit into the RAM, maybe partitioning, defraggin’ might help a bit. less diskaccess -> less cpu interrupts -> less cracks and pops. i remember halion does disk streaming and i get a few pops sometimes too.

…that aside, i wish i had 9Gb of samples to play with… :yeah:

i’m pretty much what ppl call a “performance enthusiast” and believe me when i say that my system is actually tweaked to the max - hardware and software-wise.

keith, wazzzap!

i DO believe you when you say your system is tweaked to the max. could you please let me and the others in on some of the stuff that is important to do when tweaking your system? i assume you are running XP, and i know there are several key things that can be done to improve audio related tasks.

take care m8,