The feel of a LispM/List of running machines

Chris Bitmead uid(x22068)
Mon, 05 May 1997 10:05:10 +1000

>> What I'm saying is that we can store things into UNIX files at a
>> particular level of granularity.
>My idea is only database "files" exists, e.g.  boot.db, silk.db, etc.
>Each database file can be as big or small as it needs to.
>We use the UNIX file system for those DB files.
>Eventually they might go directly to the disk as disk pages,
>but that is a *lot* of additional work, which man RDB and OODP companies
>say improves performance only around 10%.
>We might not even got that improvement, because the db files
>are primarly used as simple memory page backing store.

Perhaps the way to get the OOFS working fast is to use mmap'ed files
under UNIX. That way people can start writing apps the Right Way(tm),
very quickly.

The danger is that the semantics of an mmapped file suck as a proper
solution to the problem, and the lispvm people might get lazy and not
build in the proper vm and gc support for a real solution.

The other thing is that you can't have object level locking with
page-mapped files which is essential for a working multi-threaded