CD-ROM ISO file support is abnormally slow on DOS-based systems

[CONIGUERO]

This is neither a crash nor a usabilty bug so I'm not sure if the log applies here.

Version: 3.2.4 macOS version: 12.4

When emulating an i386 machine with any configuration (processor type, memory, network, drive types, all make no difference) the emulated cd-rom drive is extremely slow when being used by MS-DOS or any DOS-based system like Windows 3.1x

It is so slow in fact that I have to wait several seconds just to cd into any directory on D:

This is not only present in already-installed DOS but also on bootable CDs as well. The Windows 98 OEM CD-ROM, which boots a temporary DOS environment to prepare the installation, is also extremely slow to read itself

[danwdart]

This is the case with qemu - have you created an issue in qemu as well?