Subject: C414 JGSI Review
Resent-Date: Thu, 30 Sep 1999 23:18:19 -0400
Resent-From: Geoffrey Fox <gcf@npac.syr.edu>
Resent-To: p_gcf@npac.syr.edu
Date: Sun, 19 Sep 1999 00:06:58 -0700
From: "Michael O. Neary" <neary@cs.ucsb.edu>
To: gcf@npac.syr.edu

a) Overall Recommendation:

accept

b) Comments to the authors:

The paper describes a plug-in replacement for RMI, called KaRMI,
and a similar replacement for Java Object Serialization, called
UKA-Serialization. Both replacements offer significant performance
gains over Sun's implementation and seem straightforward to use
with existing Java RMI applications. KaRMI is also able to use
other communication technologies besides TCP/IP, thus increasing the
benefit for users of high-speed networks like Myrinet.

This is a well written and technically sound paper. It was fun to
read it for this review! The authors first present a detailed analysis of
the shortcomings of RMI and Object Serialization, then address each
of these problems with a suitable fix, and finally back up their claims
with an extensive set of experimental results that show the improved
performance.

The high practicality of this work is demonstrated by the simplicity with
which KaRMI can be used to replace the existing RMI in JDK.
Hopefully, some, if not all, of these improvements will make it into Sun's
next release.

Related work also seems comprehensively handled.

If anything needs to be improved, perhaps it should be Section 3.7, where
the
authors talk about design issues regarding their UKA-Serialization.
I found this section a little hard to understand without detailed knowledge
of the implementation of Sun's Object Serialization. A few code examples
might make this section easier to read.

Also, there is a grammatical mistake in the 2nd paragraph of Section 4.1:
"Making them a part of the API and thus visible at the application level,
causes that ..." where "causes that" should be replaced, e.g. by "means
that".

Finally, in their conclusion the authors state a median savings of 45% for
PCs with Ehernet, which they claim to be a sixfold improvement... Shouldn't
that
be a twofold improvement, or did the authors really mean the 85% savings for
DEC Alpha a few lines further down ?