RE: vk_l4 -- CVS Setup

[Volkmar Uhlig]

> -----Original Message-----
> From: Debian UserAd Buijsen [mailto:address@hidden 
> Sent: Monday, October 29, 2001 11:19 AM
> >> 
> >> > Version 2 of the L4 spec. has Unique IDs containing a 
> "site" field, so kernel-assisted
> >> > remote IPC was considered at a time, I presume.  A 
> "site-fault" for non-local IPC would be
> >> > one method to handle it, or a generalized form of IPC 
> redirection.
> >> 
> >> Cool. I've only read the X.0 spec, I believe. Where can I 
> find the newer specs?
> >> 
> >> -- Ian
> >> 
> 
> Version 2 is the old one;  the 'X' versions are experimental 
> and will lead to version 4, which
> seems to be in review at the moment.  Version 3 appears to 
> have been mislaid...

The site field was dropped for usability and performance reasons. A
compatible system can always be constructed using transparent proxy
threads. The advantage is one additional register (50% more) for short
IPC on x86. Version 4 will not have a site field either -- so do not
rely on it.
Version 3 was somewhere in between X.0 and V4 and retired in an
experimental state.

        - Volkmar