Intel’s
latest 64-bit systems will give little or no advantage over 32-bit
systems running application server software based on code from Java
or Microsoft.
Users have been
advised that running the latest 64-bit Itanium II systems as
application servers may not offer a sufficient performance boost to
justify the cost over existing 32-bit Xeon hardware.
Published Java
application server benchmarks show two-processor Itanium II-based
systems are inferior in cost and performance compared with
four-processor Xeon systems.
Microsoft has also
admitted its rival 64-bit .net architecture is still in the early
stages of development.
Both .net and Java
use just-in-time technology, which will need to be redeveloped to
make the most of Itanium’s Epic (Explicitly Parallel Instruction
Computing) architecture.
At last week’s
launch of the much-anticipated “Madison” release of the Itanium II
64-bit architecture, Richard Draycott, worldwide director for
enterprise servers at Intel, admitted the performance of Java on
Itanium was only now “competitive” to Xeon.
Bola Rotiba,
senior analyst at Ovum, said, “Do not move to Itanium for your
application server until the just-in-time compilers are ready.” She
said users should look carefully at which applications they plan to
deploy on Itanium II as some contain Java, which may not be able to
run optimally.
"Before you buy 64-bit Intel, understand your system fully. Check
where you have Java running," she said. Rotiba said certain
applications such as SAP now offer Java interfaces, which could be
affected by moving the application onto Itanium. But this problem
is not limited to Java. Rotiba said the just-in-time technology
used in Microsoft's .net architecture would also run inefficiently
on Itanium-based systems.
Her concerns are reflected in the latest SpecjAppServer2002 Java
benchmarks, in which Bea Weblogic Server 7.0 running on a
two-processor HP rx5670 Itanium II server gave a total operations
per second (Top) benchmark result of 408.02 at a cost of $1,075.17
(£643) per Top on HP-UX.
In comparison, the four-processor Xeon-powered IBM eServer xSeries
x360 running Websphere 5.01 on Windows 2000 Advanced server
delivered 448 Tops at a cost of $647.52 per Top.
Kieran Mockford, architectural software engineer at Microsoft, said
a 64-bit just-in-time compiler was being developed for the next
release of Visual Studio .net, but did give the release date. He
claimed the approach Microsoft is taking would allow applications
to run on any of the supported 32-bit and 64-bit systems without
modification.
The problem with Java on Itanium
One problem with running Java on Itanium is the complexity of
Intel's Epic 64-bit architecture. Epic expects a program's
instructions to be ordered in a way that allows the chip to run
several instructions at the same time. When a C or C++ application
is converted to an executable program, a compiler converts the
source code into machine instructions and optimises the performance
for Epic.
Unfortunately, the
Epic architecture does not lend itself well to just-in-time
compilers used for Java because these generate a continuous stream
of instructions.