CPU spikes with VST plugin.

[Ulg]

I use LMMS with the Synth 1 VST plugin. Periodically (every few minutes), I get cpu spikes and the audio distorts. Sometimes it is quite bad and the program freezes up, crashes, or I have to manually close it with the task manager. I can't figure out if this is due to the VST or LMMS. The problem also occurs if I use the samples (it's actually quite worse when using these).

Here are the specs on the computer that I have it installed:

OS: Windows 7 64 bit
CPU: Intel Centrino
RAM: 4 GB

I have LMMS on two computers with pretty much the same specs except my primary machine has the 64 bit version of windows and the other machine has 32 bit. The problem isn't as bad on the 32 bit machine. I believe the problem could be the CPU, but I haven't been able to find the actual list of technical specifications the program requires.

It would be appreciated if anyone can shed some light on this issue.

[musikbear]

difficult..
Sounds like you have a fine pc.. lots of ram, at least
Doubt an inferior cpu would be in a 4 gb ram pc..

Heres some other 'things'
post your:

*lmms vers
*lmms sound device chosen
*if any -screenshots of error
*if relevant, demo mmp
*perhaps a sound-file

[Ulg]

Version: 1.0.3

I'm not totally sure, but I don't think I had this problem on the older version.

The sound device I am using is VeSTige VST plugin host and I am running the Synth 1 VST from KVR Audio. This is a good VST, a lot of people use it.

I can't post a screenshot right now because I am on the 32 bit machine, and like I said, it generally runs fine, so I can't recreate the problem. I'll post one later.

The sound is good and my tracks have no problem when I export, it's just when I am recording and playing the instruments. The problem usually occurs when I drag a preset from the VST to the Beat/Bassline Editor and when I drag not around on the piano scroll.

I recently reinstalled windows on the 64 bit machine and that did not fix the problem.

[Ulg]

Here is a screenshot of the problem. While this is happening, the audio "skips".

http://i.imgur.com/upOurnv.png

[musikbear]

The sound device I am using is VeSTige

no no, thats the instrument. Your sound-device is chosen in the settings dialog:
https://lmms.io/documentation/LMMS_Sett ... o_Settings
for windows we recommend SDL

If this only happens when you drag presets or trcks, then i would dare to say, that it could be a cpu issue- In general i dont drag stuff around during play, because that has been a troublemaker, in the earliest versions, so i have made it a habbit not to (except notes, lmms does that just fine)
But a lot of stuff happens when an instrument is moved, or a new is added, so thats best done, in idle
But check the sound-device, i dont think it will fix spiking, but if you do have sdl, then you will get better sound, with sdl :)

[Ulg]

Sorry about the confusion, but, yes, I am using SDL.

As far as the dragging goes, I find it sometimes necessary because when I press record, I am not ready to start playing and I wait for the metronome to count for a few beats. After I record, I move everything back to the beginning. Also, sometimes, a note might be off and I will edit it.

[musikbear]

then im pretty much out of 'good' idear, except -Make sure that nothing else runs on the pc, and perhaps most important:

Disable autoamtic backups!

Theat feature uses a lot of cpu in bursts, and could be the reason

[tresf]

We are aware and working on it.

https://github.com/LMMS/lmms/issues/967

For the short term, check out that VBScript I wrote in the original bug description (or set RemoteVSTPlugin to high/realtime priority via task manager.)

Today I found some functions from Microsoft which should help. Those changes won't be in until version 1.2, unless we decide to back port them to 1.1.