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Having been involved in MD Nastran performance tuning and benchmarking activities on Sun hardware for many years it always catches my attention when I see some stand-out performance on new hardware.  I saw some of this exceptional performance during some recent MD Nastran benchmarking I did on the new Intel Xeon Processor 5500 Series (aka Nehalem) found in the Sun Fire X4270 server.  This benchmarking effort was part of a larger effort I was involved in to gather benchmarking performance data across various Sun hardware configurations--my goal was to study the effects on MD Nastran performance (elapsed and cpu times ) for different processors, disk,  and memory configurations.  I saw exceptional performance (reduced elapsed times) on the Sun Fire X4270 compared to all the various platforms and configurations I tested.   As one example from my benchmark study I chose the following X4150 machine configuration for this blog:

    Sun Fire X4150 Server

    2x Xeon X5460 3.1 Ghz processors, 24GB RAM

    4x 146GB 10K RPM SAS drives

    OS: Solaris 10

     The new Sun Fire X4270 configuration:

     Sun Fire X4270

     2 Xeon X5570 2.9 Ghz processors, 24GB RAM

     4x 146 10K RPM SAS drives

     OS: Solaris 10

On both servers I used one disk for the Solaris 10 OS, MD Nastran binary, and the standard MD Nastran *.f04,*.f06, and *.log output files.  I configured the remaining  disks with ZFS and used these for the MD Nastran database files (more on ZFS later).

The table below shows the "% reduction in elapsed time" for the MD Nastran MDR3 benchmarks on the Sun Fire X4270 compared to the Sun Fire X4150:

getrag	gm20a_1_1	md0mdf1_1	xl1fn40	vl0sst1	xl0imf1	xl0tdf1_1	xx0cmd2_1
34%	27%	32%	32%	16%	55%	17%	35%

 A description of these MD Nastran MDR3 benchmarks can be found on MSC.Software's performance web site.  

 

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As I mentioned earlier, this performance data came out of a larger study I was involved in to look at various machine configurations and their effect on MD Nastran performance.  I'll blog in more detail on that study in a future blog--here's a few highlights:

1. Solid State Drive (SSD) performance vs SAS disk:

During my performance study with SSD's I saw some noteworthy performance improvements (elapsed time reductions) on some of the above individual MD Nastran benchmarks and also when I ran a combination of these benchmarks concurrently on the same machine.  In some cases I saw up to a 56% reduction in elapsed times when using the SSD's compared to the internal SAS disks --with the amount of reduction corresponding to the amount of I/O and memory used by the benchmark(s).  For example, the relatively large MD Nastran  DMP (Distributed Memory Parallel) benchmark "xx0cmd2_8,  DMP=8" was 49% faster (elapsed time) using the SSD's compared to the internal SAS disks, while other smaller benchmarks like the "getrag" benchmark showed a 19% reduction in elapsed time.  I was also able to get significant performance improvement using the SSD's when I ran a combination of Nastran benchmarks concurrently on one machine.  For example, running 3 benchmarks concurrently (two getrag jobs and one xl1fn40 job), which together utilized 20Gb of memory and generated 1TB of total I/O, I saw a 44 - 56% reduction in elapsed time with the SSD's compared to the internal disks.  The reason for the range of 44-56% is explained in the next section below on "ZFS Intent Log (ZIL)".

Here's the configuration I used for this SSD benchmarking:

     Sun Fire X4270

     2 Xeon X5570 2.9 Ghz processors, 24GB RAM

     4x 146 10K RPM SAS drives (formatted with ZFS (Raid 0))

     3x SSD's (32GB SSD's) (formatted with ZFS (Raid 0))

     OS: Solaris 10

2. ZFS Intent Log (ZIL):

I've blogged in the past on the benefits and "ease-of-use" of using "ZFS with MD Nastran".

Recently I discovered a configuration option with ZFS that's worth noting related to what's called the ZFS Intent Log (ZIL).  By simply turning off the ZIL I was able to turn the 44% reduction in elapsed time (mentioned above in my discussion on SSD performance) into a 56% reduction.  The ZIL is a mechanism to guarantee ZFS in terms of writes in the event of a machine crash.  However, if you're running an MD Nastran "scratch (scr=yes)" job then you will probably be comfortable experimenting with ZIL turned off to see if your particular mix of jobs will benefit.  I'm currently in the process of running various Nastran benchmark combinations with ZIL turned off and will post the results of that study in a future blog.

To turn off the ZIL edit the /etc/system file and add the following:

set zfs:zil_disable=1

 

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For more information:

1. Sun Fire X4270 server 

2. MD Nastran 

3. Sun Fire X4150 server 

4. Solaris 10 OS 

5. Solid State Drive (SSD)