second call for feedback on Naiad design

[Craig Latta]

Hi Igor--

 > > Every time the subject memory adds, changes, or removes a class
 > > definition, method, author, comment, tag, or module, or makes a
 > > checkpoint (i.e., makes an edit), it adds the appropriate editions
 > > to the history memory via remote messages. The history memory
 > > snapshots itself after every edit, so as to provide crash recovery
 > > support.
 >
 > Hmm, this could be a bit heavyweight. A history can grow to multiple
 > hundreds of megabytes, then, imagine how slow it could be when you
 > have to snapshot full image at every change.
 >
 > As optimization, it could use a temporary file(s) to save incremental
 > changes, to avoid snapshotting at each edit. Then it can do full
 > snapshots when incremental file grows bigger than certain amount or by
 > direct request to clean-out incremental storage.

      Well, these days even memories that large have snapshot times that 
fall within the idle intervals of a development system. But assuming 
it's a problem, I'd rather divide the history memory into several 
memories (probably by how utilized the editions are). I can also imagine 
limited periods where one is willing to forego edition-by-edition crash 
recovery (e.g., when installing a set of changes which are meant to be 
atomic). The subject could keep track of the change order and report it 
to the history memory later, if desired.

 > Since there is no single, global SystemDictionary its pointless to
 > discuss the cos and pros of namespaces. In your system each
 > class/module effectively is name space, the question, of course, how
 > to reflect the new capabilities of system in a way which don't shatter
 > the [foundation] of smalltalk syntax and its spirit.

      Well, my proposal doesn't change the syntax at all, although it 
does impose additional responsibilities on the tools. Since the 
existence of a single system dictionary was always an implementation 
detail and never part of the fundamental spirit of the system, I think 
we're okay there, too.


      thanks!

-C

--
Craig Latta
improvisational musical informaticist
www.netjam.org
Smalltalkers do: [:it | All with: Class, (And love: it)]