Core type doesn't get shown in the app title bar.
If you just enter "core" at the command prompt what is the response?

You probably don't have a dynamic core. Typing "core dynamic" in Dosbox might reveal that. Reason is that you are using Dosbox 0.74 and its dynamic core was not compatible with 64bit, so the package manager might have patched that out. See if you can get Dosbox 0.74-2 running which has better 64bit support (I think jmarsh here played a role in that, too 😉)

jmarsh wrote:

Core type doesn't get shown in the app title bar.
If you just enter "core" at the command prompt what is the response?

Really? I remember that in the past (maybe in 0.73?) when it actually switched to dynamic core, the cycles did not show up and I couldn't increase or decrease the speed of the execution. So I assumed that since now I can see the cycles and even decrease/increase them, then dynamic is not really on.

"core" returned "auto" but it seems I can make it return dynamic as well: https://imgur.com/fCQyjkP

Dominus wrote:

You probably don't have a dynamic core. Typing "core dynamic" in Dosbox might reveal that. Reason is that you are using Dosbox 0.74 and its dynamic core was not compatible with 64bit, so the package manager might have patched that out. See if you can get Dosbox 0.74-2 running which has better 64bit support (I think jmarsh here played a role in that, too 😉)

Please see the screenshot above. It seems like core can be set to dynamic. But did the title bar behavior and the ability to change cycles change in the 0.74 version?

Perhaps I can try 0.74-2 but I need to figure out where to get compatible deb. The debian package suggested in the download page seems to be dosbox_0.74-4.2+deb9u1_amd64.deb which seems to be the same version that I have now. Otherwise I'll have to build it from source.

You might be misremembering the cycles and core stuff. Cycles were always adjustable and that was not impacted by the core.
And yes, best look for where you can grab Dosbox 0.74-2. I'd even suggest grab the SVN and build it yourself. It's rather trivial on Linux to do this

If "core" returns dynamic then it's definitely using the dynamic core.
To confirm you could try running something like pcpbench, first with "core normal" then again after "core dynamic" and see what the difference in speed is.

Not sure if debian has updated their package but last I checked, their 64-bit build was out-of-date and the dynamic core liked to crash (misaligned stack causes segfaults for some fpu ops) so finding a newer build (or using their 32-bit package instead) might be a good idea.

Hmm you are right. I am using dynamic core. Just typing core dynamic and core normal before start some of Phil's benchmarks made a huge difference. I also found out that opengl and openglnb is the fastest on my machine.

Thank you very much for the help.