Re: is there a version of unix written in Ada

[Paul Rubin <no.email@nospam.invalid>]

DrPi <314@drpi.fr> writes:
> Address translation is also a security feature. One process can't
> access data of another process. What about this with Singularity ?

The compiler statically verifies that you can't access data of other
processes.  All the code is written in a dialect of C# that is analagous
to SPARK/Ada, that does the verification.  Also, it's not a consumer
operating system that runs all kinds of hostile applications, browsers,
etc.

> TLB tables are reloaded when switching from one process to another.

If those tables are not there in the first place, there is nothing to
reload.

> I don't get the point on translation delay on every memory access
> since the address translation is done by efficient specialized
> hardware.

It still adds a delay, especially in the case of a cache miss.

> Have you had a look at Ressource manager, memory tab in Windows 10 ?

This isn't about Windows.  If your application needs data on disk, it's
better to manage that yourself rather than leave it up to the OS, which
knows nothing about your application's behaviour.  That's in any rate
similar to the argument that Ada users make against garbage collection.
OTOH, it looks like Singularity is garbage collected, so there's that.