Rekordbox 5.0 library performance.

@Rod > Are you loading the tracks from a USB drive? What kind of device is it (make / model)?

whether its from the usb or switching between playlists on my computer it sometimes lags out, its not doing it today. might only do it when i have the usb in?. ive also noticed that syncing is taking a really long time.If i drag and drop my library it takes about 4 min to copy stuff in windows but rekcordbox takes upwards of an hour to write it.

its a Samsung 128gb bar
gets about 140mb/s read and 50-100mb/s write when i transfer stuff in windows.

What is the model of that Samsung drive? Not all drives are created equal, and 50-100MB/s is a pretty low write speed.

I've had this same issue -- Rekordbox 5 has significant but intermittent lag problems where the previous version did not (or at least not nearly as bad). It leads to long (as long as 10-20 seconds sometimes) lag that gets worse until I restart the application, that is especially bad when loading tracks, placing hotcues, or sometimes just trying to pause the track while playing. I realized today that it might be at least partly related to how Rekordbox is drawing the waveforms and artwork on a playlist. When I try to scroll through a playlist, the waveform previews redraw VERY slowly, and it looks like it's laying the waveform down one piece at a time and then finally lays down the hotcue previews. Displaying the artwork previews similarly takes a long time. I've noticed performance is improved significantly when I hide the waveform and artwork preview columns, which isn't really a great long-term fix. Oddly, it also seems it could be related to something going on with my library, since when I move the library over to a Window Surface Book, I have the exact same issues, but it doesn’t seem to be related to specific corrupted tracks somewhere in the library because when I create a new library and only add a few tracks, it still occurs.

@Rod I'm curious whether you've tried any similar troubleshooting, and whether you're still experiencing your issues.

For reference, the machine is a reasonably capable Core i7 MacBook Pro 15", GeForce 650M and Intel HD 4000 graphics, with 8 GB RAM running High Sierra. Changing the waveform drawing rate to medium in preferences doesn't seem to make a difference (other than making the live waveform look worse when playing a track).

@Keith > I would direct you to please file an inquiry ticket here and our rekordbox support team will be able to gather some additional information to assist you in resolving that issue.