Minix Strengths and Weaknesses ?

[Patrick McC^very]

Hi Everyone

Could you help me understand the limits Minix has now. I don't mean this to be negative, I just need to know what needs to get done and I need to guesstimate when those things will get done and if I can help.

I am eagerly waiting for David's new network stack, I am sure it will be great.

Of these things are there known weak points:

cdrom support is not great because we don't have full ISO support. However is it unfair to say that it is buggy? Is our support old but reliable?

Is native disk support a problem? I know we don't have much support for non-native file systems but I don't care.

How is driver support for ISA and PCI ?

How is port-like drivers for serial and parallel ?

I know we don't have USB and I don't care.

How is support for PS2, any major bugs with these mice and keyboards?

How about video support, if I am just using plain old VGA, am I pretty safe?

I know the kernel is not great but is it not good enough for now? Is it causing major problems?

Thanks for reading

[Jean-Baptiste Boric]

Hi,

 

cdrom support is not great because we don't have full ISO support. However is it unfair to say that it is buggy? Is our support old but reliable?

I rewrote the current ISO 9660 file system server, which supports the Rock Ridge extensions. Compared to its previous incarnation, it works fine. I'll admit it's a bit of a hack on the inside (for various technical reasons), but it's solid enough to be the root file system for the installation CD.

The poor reputation of ISO 9660 on MINIX comes with the previous file system server incarnation, which was effectively completely broken for years. There has been no official release with the new, rewritten one yet, so the poor reputations remains.

 

Is native disk support a problem? I know we don't have much support for non-native file systems but I don't care.

There's support for ATA and AHCI drives for physical hardware. People do run into issues with disk controllers from time to time, but I think it's mostly due to buggy hardware rather than MINIX bugs for the most part (we don't have as many workarounds for bad hardware as the more traditional operating systems do).

We don't support SCSI, SAS, NVMe, MMC (on i386) or anything else since we don't have drivers for those yet. I don't think we can go beyond 2 TiB for now either.

 

How is driver support for ISA and PCI ?

It's there. We support a fair range of both common and retro ethernet cards. We have a couple of drivers for audio cards, but the old MINIX sound subsystem needs a rewrite to be more NetBSD-like.

Beyond that, while we do support ISA and PCI we just don't have tons of drivers for them yet.

 

How is port-like drivers for serial and parallel ?

I expect that they just work, but we only support the IBM PC ones (we don't have drivers for the PCI cards variants). Haven't tested them on real hardware yet.

 

How is support for PS2, any major bugs with these mice and keyboards?

I never had an issue with those yet.

 

How about video support, if I am just using plain old VGA, am I pretty safe?

The MINIX tty server only supports VGA textmode on i386, no framebuffer here (another area that needs improvement). We do have X11, but I'd wait until the new network stack branch is merged before using it since it seems to be more stable with it.

 

I know the kernel is not great but is it not good enough for now? Is it causing major problems?

It works. Just don't take a look inside :-)

The problem is that it's old, rusty and not very pleasant to work with, but it's dependable. We probably have performance problems hidden inside it and it's the only reason why we don't have SMP (we did have SMP a while back, but it bit-rotted).

Clearly our current micro-kernel *implementation* is not the best piece of software inside MINIX 3, but so far it serves our purposes well.

[Patrick McC^very]

Thanks very much Jean-Baptiste !

let me pitch in by testing parallel and serial ports on actual hardware.

[Denis Obrezkov]

четверг, 30 марта 2017 г., 4:07:09 UTC+3 пользователь Patrick McC^very написал:

For example, it doesn't support NFS, thus, on beaglebone you have to use SD card for all

your partitions. It's not very good for SD cards.

Another problem, is a lack of vision and a roadmap. For example, I don't know what is the main 

objective of the project. And I didn't figure it out after several topics of discussion.

[Chris Card]

 the main goal is 42