Performance Tuning Siebel Software on the Sun Platform

1 <strong>Tuning</strong> for Price/<strong>Performance</strong>: Summary
The Solaris Operating System is the cornerstone software technology that enables Sun
to deliver high performance and scalability for <strong>Siebel</strong> applications; and the OS contains a
number of features that enable customers to tune for optimal price/performance levels.
Among the core features of the Solaris OS that contributed to the superior results
achieved in the tests:
Solaris MTmalloc: A standard feature with the Solaris system was enabled on the
<strong>Siebel</strong> application servers. This is an alternate memory allocator module that was built
specifically for multithreaded applications such as <strong>Siebel</strong>. The MTmalloc routines
provide a faster, concurrent malloc implementation. This feature resulted in lowering
CPU consumption by 35%. Though memory consumption doubled as a side effect,
overall price/performance benefits are positive. There have been improvements made on
MTmalloc in Solaris 10 OS which reduce the space-inefficiency penalty. More details on
this topic are available in Section 7.1.1.
<strong>Siebel</strong> Process Size: For an application process running on the Solaris OS, the default
setting for stack and data size is unlimited. We found that <strong>Siebel</strong> software running with
the default Solaris system setting caused bloated stack size and runaway processes that
compromised scalability and stability of <strong>Siebel</strong> on the Solaris OS. Limiting the stack size
to 1MB and increasing the data size limit to 4GB resulted in increased scalability and
higher stability. Both adjustments let a <strong>Siebel</strong> process use its process address space
more efficiently, fully utilizing the total process address space of 4GB available to a 32-bit
application process. A significant drop in failure rate of transactions (only eight failures
out of 1.2 million total transactions!) was observed as a result of these two changes.
More details on this topic are available in Section 7.3.
Solaris Alternate Threads Library: Solaris 8 OS provides an alternate threads
implementation with a one-level model (1x1) in which user-level threads are associated
one-to-one with lightweight processes (LWPs). This implementation is simpler than the
standard (MxN) two-level model in which user-level threads are multiplexed over
(possibly) fewer LWPs. When used on <strong>Siebel</strong> Application Servers, the 1x1 model
provided good performance improvements to the <strong>Siebel</strong> multithreaded applications. More
details on this topic are available in Section 7.1.2.
Solaris Multiple Page Size Support (MPSS): A standard feature available in Solaris 9
OS and subsequent versions, MPSS gives applications the ability to run on the same OS
with more than one page size. Use of this Solaris library allows a larger heap size to be
set for certain applications, which results in better performance due to reduced TLB
miss%. This feature was enabled on the Oracle server and resulted in performance
gains. More details on this topic are available in Section 7.6.4.
Solaris Resource Manager was used on all tiers of the setup to efficiently manage CPU
resources. This resulted in fewer process migrations and translated to higher cache hits.
<strong>Performance</strong> <strong>Tuning</strong> <strong>Siebel</strong> <strong>Software</strong> on the Sun Platform Page 7