By 11111 on Oct 12, 2009
Significance of Results
The Sun Storage F5100 Flash Array can greatly improve performance over internal hard disk drives as shown by the I/O intensive ANSYS MCAE application BMD benchmark tests on a Sun Fire X4270 server.
Select ANSYS 12 BMD benchmarks were run on a single Sun Fire X4270 server. These I/O intensive test cases were run to compare the performance of conventional high performance disk to Sun FlashFire technology.
The ANSYS 12.0 module is an MCAE application based on the finite element method (FEA) of analysis. This computer based numerical method inherently involves a substantial I/O component. The purpose was to evaluate the performance of the Sun Storage F5100 Flash Array relative to high performance 15K RPM internal stripped HDDs.
The Sun Storage F5100 Flash Array outperformed the high performance 15K RPM SAS drives on the "BMD-4" test case by 67% in the 8-core/8-thread server configuration.
The Sun Storage F5100 Flash Array outperformed the high performance 15K RPM SAS drives on the "BMD-7" test case by 18% in the 8-core/16-thread server configuration.
ANSYS 12 "BMD" Test Suite on Single X4270 (24GB mem.) - SMP Mode
Results are total elapsed run times in seconds
|Test Case||SMP||4x15K RPM
72 GB SAS HDD
striped HW RAID0
r/w buff 4096
Results and Configuration SummaryHardware Configuration:
Sun Fire X4270
2 x 2.93 GHz QC Intel Xeon X5570 processors
24 GB memory
4 x 72 GB 15K RPM striped (HW RAID0) SAS disks
20 x 24 GB flash modules
O/S: 64-bit SUSE Linux Enterprise Server 10 SP 2
Application: ANSYS Multiphysics 12.0
Benchmark: ANSYS 12 "BMD" Benchmark Test Suite
Benchmark DescriptionANSYS is a general purpose engineering analysis MCAE application that is based on the Finite Element Method. It performs both structural (stress) analysis and thermal analysis. These analyses may be either static or transient dynamic and can be linear or nonlinear as far as material behavior or deformations are concerned. Ansys provides a number of benchmark tests which exercise the capabilities of the software.
Please go here for a more complete description of the tests.
Key Points and Best Practices
The performance of Ansys (IO-intensive MCAE application) can be increased by reducing the IO demands of the application by increasing server memory or by using SSDs to increase the bandwidth and reduce the latency. The most I/O intensive case in the ANSYS distributed "BMD" test suite is BMD-4 particularly at the (maximum) 8 core level for a single node.
- Large memory can cache file accesses but often the size of ANSYS files grows much larger than the available physical memory so that system file caching is not able to hide the I/O cost.
- For fast ANSYS runs the recommended configuration is a RAID 0 setup using 4 or more disks and a fast RAID controller. These fast I/O configurations are inexpensive to put together for systems and can achieve I/O rates in excess of 200 MB/sec.
- SSD drives have much lower seek times, use less power, and tend to be about 2X faster than the fastest rotating disks for sustained throughput. The observed speed of a RAID 0 configuration of SSD drives for ANSYS simulations has been nearly as fast as I/O that is cached by large memory systems. SSD drives then may be the most affordable way to extend the capacity of a system to jobs that are too large to run in-core without incurring the performance penalty usually associated with I/O demands.
More About The ANSYS BMD "Distributed" Benchmarks
ANSYS is a general purpose engineering analysis MCAE application that is based on the Finite Element Method. It performs both structural (stress) analysis and thermal analysis. These analyses may be either static or transient dynamic and can be linear or nonlinear as far as material behavior or deformations are concerned.
In the most recent release of the ANSYS benchmarks there are now two test suites: The SMP "BM" suite designed to run on a single node with multi processors and the DMP "BMD" suite intended to run on multi node clusters but which can also run on a single node in SMP mode as in this study.
- The test cases from both ANSYS test suites all have a substantial I/O component where 15% to 20% of the total run times are associated with I/O activity (primarily scratch files). Performance will be enhanced by using the fastest available drives and striping together more than one of them or using a high performance disk storage system with high performance interconnects. When running with the SX64 build a ZFS system might be a good idea to employ.
- The ANSYS test cases don't scale very well (BMD better than BM) ; at best on up 8 cores.
- The memory requirements for the test cases in the ANSYS BMD are greater than for the standard benchmark test suite. The requirements for the standard suite are not great requiring less than 3GB.