Manually installed DOS CDs cause lag/stutter

[KamiLordus]

While testing DOS games on CD, I noticed that almost every one has a strange lag/stutter a few moments after launching the game.

Most often, the lag appears within the first minute of starting the game.
I spent a lot of time trying to figure this out and testing various DOSbox Pure settings. At first, I thought it was a problem with the sound settings, then with performance, but no.
Everything points to the problem being "manually" installed games from the CD and how DOSbox Pure handles the .zip file.

The problem occurs when we unzip the game (in my case, bin/cue) and install it using DOS. DOSbox Pure creates a directory in RA/Save/DOSbox Pure/gamename.pure.zip.

Interestingly, if we rename this zip file to gamename.zip, create a CD folder containing the game's cue/bin files, and add them to the same folder, the game runs without any problems. No lag/stutter.

I'm no expert, but it seems to me that Dosbox Pure handles the game in a .zip format that contains all the files much better than when the bin/cue and gamename.pure.zip are in separate locations. Even if you set the RA option to install the files in the same location as the bin/cue.

Tested games:
Death Rally - stutter after few second after race start
Earthworm Jim 2 - stutter after few second after game start
Duke Nukem 3D - same
Descent 2 - huge stutter in first 30sec-1min after game start

my log:
retroarch__2026_02_16__21_44_22.log

Edit:
During extended testing, I noticed something else:
When the game image (bin/cue) itself is compressed into a .zip, and then the game is installed to RA/saves/Dosbox pure, the exact same thing happens as described earlier. Although the core uses the "caching zip folder" method, it doesn't change anything and the game continues to stutter.
It seems the only way to play without stuttering is to put all the files in one place.