r41Gamma1

[Chris Muller]

I have just posted r41Gamma1 Monticello Configuration to the
"MagmaTester" project of SqueakSource.  I have been very busy since
the last r41Beta11 was posted.

I have made significant updates for this new version, including some
changes you will want to be aware of for potential changes to your
application.  Here is a summary of the changes:

More Robust
========
	- New #testMisbehavingSession ensures server correctly deallocates
sessions when their challengingEntries exceeds the specified limit.
	- Independent Magma servers (not clients) have always operated with a
relatively low memory footprint, but nevertheless now monitor memory
utilization relative to capacity of the VM it's running in.
"Capacity" is determined by parsing the '-memory' option passed to the
vm in the command-line, or 450MB if no command-line option was
specified.  If memory utilization exceeds capacity, the oldest session
is purged to make room.

Better support for headless operation
======================
	- Looks for either of 'display=none' or '-headless' in the
command-line arguments to determine whether running headless.
	- No MaWarning will open a debugger when the image was launched with
a headless option.  Any signaled MaWarning will be resumed
automatically (#defaultAction).
	- An extra-safe headless guard; if user forgets to connect a session
in a headless client, connect as 'unnamed' for them.

New Semantics
==========
	- When a session is in a transaction for too long, the server must
eventually clean up in-memory resources associated that session.  Up
until this r41Gamma1 update, if the client was not truly "dead" but
instead just taking a long time to commit, a MagmaSessionLost would
have been signaled when the session finally did commit.  At that
point, to avoid losing the work, the client would then have to
reconnect, send #begin again (which would update their image with
other sessions changes), followed by #commit.
	Now this "recovery" scenario is performed automatically.  Lost
sessions are automatically reconnected, including reestablishment of
the transaction!  Local-only changes are untouched but other parts
changed by others are brought up to date on the reconnection,
invisibly to the client.
	- The nice side-effect of this is transactions can also span
*deliberate* session reconnections, including even when an image saves
and exits, then resumes later, the transactions is automatically
"restored".  Again, noting of course, that the persistent model is
"rolled forward" on the reconnection.
	- At last, refreshPersistentObjectsEvenWhenChangedOnlyByMe preference
has been removed.  When crossing a transaction boundary, "updates" by
other sessions are always merged into the local persistent model.  But
this option has always addressed whether Magma should revert
*local-only* changes for begin, abort and commit-conflict that were
not changed by other sessions.  Now, it operates as follows:

		abort - always update, always revert.
		begin - always update, never revert.
		commit (conflict) - always update, never revert.
		commit (successful) - always update (nothing to revert)

	This is much less awkward than the old boolean preference.

	- Finally removed the experimental MagmaOfflineObject and associated
'offlineResults' from MagmaForwardingProxy.


Several enhancements to the "Ma Client Server" framework
====================================
	1) A new abstract superclass for all requests MaClientServerRequest
now knows its #lifecycle attributes and #clientConnection, providing
network-layer access to the application-server program.  Useful for
the application to deallocate socket connection resources after a
timeout period of inactivity.  (Obviously, this was instrumental in
the resource reclaimation associated with old purged sessions in
Magma).
	2) Removed MaNetworkError, now just using NetworkError.
	3) Moved "Ma Client Server"-level statistics to Ma client server
package; to the MaRequestServerConsole superclass of the
MagmaServerConsole so "Ma Client Server" applications independent of
Magma will have the informative statistics available to them for
"free."
	4) Added a "idleTimeHistory" to MaServerStatistics.  This represents
the time elapsed between requests, useful for interpreting
server-load.

Miscellenaous Improvements
=================
	- Converted MagmaSession class>>'ConnectedSessions' to a
SortedCollection for rendering in the console UI.
	- Now including the MagmaClientConnection in the commit log, so there
is not only a time-stamp record but also "who".
	- Added ability to check, from the client, whether a MagmaCollection
is locked (due to index being built), and what session has it locked.
See MagmaSession>>#isLocked and #locker.
	- Renamed Object>>#session to Object>>#magmaSession.  It is too
inconsiderate to consume such a generic api.
	- Now using lighter-weight Mutex instead of Monitor for critical code sections.

Fixes
====
	- Fix for accessing ForwardingProxy whose session has been disconnected.
	- Several bug fixes!

Cheers!
  Chris

PS - The exact packages:

Ma exception handling-cmm.30
Ma base additions-cmm.109
Ma proxy support-cmm.34
Ma traverse object graphs-cmm.24
MaFixedWidthReport-cmm.4
Ma Statistics-cmm.10
Ma object serialization-cmm.180
Collections-BTree-lr.68
Ma special collections-cmm.92
Ma client server-cmm.163
WriteBarrier-pmm.26
Magma client-cmm.324
Magma server-cmm.283
Ma Armored Code-cmm.123
Ma Squeak domain-cmm.5
Ma special collections tester-cmm.11
Ma object serialization tester-cmm.17
Magma tester-cmm.291