Performance Comparison: Sun SPARCstation 5 versus Intel Pentium 90

by Thomas W. Barlock and David S. Lindsay

Is a workstation faster than a high-end PC of similar price? There are varying claims by different manufacturers. We decided to find out by comparing an entry-level workstation and reasonably high-end PC. For the entry-level workstation, we chose the Sun SPARCstation 5 with a 70-MHz clock and 32 MB of memory, which cost $5664. For the PC, we selected a Pentium-based system with an internal 90-MHz clock and a frequency divider that reduced the external clock speed to 60 MHz. It had 32 MB of memory and cost $3989. To supplement the original hard-disk drives, we installed 4-GB Seagate drives in both machines. The database, user's home directories, and data files used for the tests resided solely on the Seagate drives.

We tried to use the same operating system (Solaris 2.4) on both machines, but, of course, some variations had to occur since the chips execute different instruction sets.

We configured each machine with 32 MB of memory - enough to run most of our tests with up to 32 simulated users. Because of time considerations, we ran most of the tests using only 1, 4, 8, 12, 16, 20, 24, 28, and 32 users.

We used the Neal Nelson Remote Terminal Emulator (RTE) to generate the commands and to measure the response times. For each test, the RTE started all the users simultaneously, emulated the desired number of users, and measured all the response times.

To compare these two machines (see Figure 1), we ran several tests using the following real-world software:

Informix database.
Oleo spreadsheet.
Software-development commands.
SPSS statistical analysis.
Frequently used UNIX system commands.
WordPerfect word processor.

While this selection should allow you to pick and choose the tests that most closely approximate your situation, in this article, we'll focus on the results of tests that use software-development commands. For results from the other tests, please contact us.

The test suites were conducted "categorically," which means two things: Every user executes the same RTE script, and every user simultaneously executes the same instruction. Solaris's default kernel configuration was used on both machines.

In the software-development-command portion of the tests, the scripts edited a C program containing 11,229 lines and 333,146 bytes, used the stream editor and program checker, looked at the space and files on a directory structure with 3016 files in 64 directories, and converted, compressed and compared files containing 8000 lines and 400 KB of data.

  Manufacturer:         (a) Sun Microsystems   (b) Intel

  Model:                    SPARCstation 5         Plato Motherboard
  Price we paid:            $5664.00               $3989.00
  CPU:                      microSPARC II          Pentium 
  CPU speed:                70 MHz                 90 MHz (internal)  
                                                   60 MHz (external)
  RAM:                      32 MB                  32 MB
  Number of CPUs:           1                      1
  Level 1 cache             24 KB                  16 KB
  Level 2 cache             0 KB                   256 KB
  Ext. disk-drive model:    Seagate ST-15150N      Seagate ST-15150N
  Capacity:                 4.0 GB                 4.0 GB
  Rotation speed:           7200 rpm               7200 rpm
  I/O controller:           Sun Microsystems       BusLogic
  Model:                    Internal to SPARC 5    BT-956C PCI
                             motherboard       
  Interface type:           SCSI-II                SCSI-II
  Operating system:         SunSoft Solaris 2.4    SunSoft Solaris for x 86 2.4

Figure 1: Environment configurations; (a) workstation; (b) PC.


Results

Each measurement category had hundreds of individual tests. All together, we had almost 2000 timings for the SPARC 5 and the same number for the Pentium. To determine the relative performance of these machines, we needed the ratio (Time on the SPARC 5)/(Time on the Pentium). Since performance is inversely proportional to time, this ratio represents the performance of the Pentium relative to the SPARC 5. But we didn't have one ratio, we had thousands.

To analyze the data points, we could have taken the average, but the average doesn't tell the whole story, and can be very misleading. We decided to analyze each measurement category separately. We plotted all the associated performance ratios in ascending order and immediately uncovered invalid data points.

One problem was that the RTE measured the response times using "clock ticks" set to four per second for many of the tests. Very short measurements - say, half a second - were therefore imprecise. So we eliminated any test where the result measured less than one second.

But there were other invalid data points. For example, while a database runs, the database manager occasionally writes its log file. The user usually has no control over logging, and if it happens during a performance test, that test is invalid. Similar problems may occur with other applications. We therefore eliminated the best and worst 5 percent of the remaining data from each category. Still, one category showed a few badly skewed performance ratios. For that category, we eliminated the best and worst 10 percent of the data.

Figure 2 is a graph of the performance ratios for the software-development-commands category, with outlying data deleted. The vertical axis of the graph is the performance ratio; the horizontal axis shows the test number. Table 1 presents the ten highest and lowest performance ratios we graphed for the software-development category. The table contains brief descriptions of each test.


Script  Meas.  Description             No.      Sun      Intel       Ratio:    
  No.    No.                          Users     Resp.    Resp.     Intel/Sun 
 
 343     3     Copy two files           4       2.37      2.37       1 
               to a directory  
 343     5     Split a 8000-line       32      17.75     17.75       1  
               file
 341     3     vi: put 1000 lines       4       9.18      9.06       1.01  
 343     4     sum two files           28      10.83     10.58       1.02 
               (800,000 char.)  
 341     3     vi: put 1000 lines      32      67.75     65.82       1.03  
 343    10     grep two files          28      12.16     11.74       1.04
 343    10     grep two files           8       3.43      3.31       1.04  
 343     4     sum two files           16       6.50      6.23       1.04  
               (800,000 char.)  
 343     4     sum two files           20       7.96      7.62       1.04  
               (800,000 char.)  
  
 343     3     Copy two files          28      17.04     16.25       1.05 
              to a directory  
 344     4     List directory to file   1       8.75      4.75       1.84  
 342     1     lint 333K program       12     150.04     80.43       1.87  
 341     4     vi: delete 2000 lines   32       4.28      2.19       1.95  
 344     4     List directory to file   4      32.87     16.81       1.96  
 341     4     vi: delete 2000 lines   16       2.78      1.42       1.96
 344     3     Sort file               28     568.12    280.11       2.03  
 343     8     Character dump of file  16     166.06     68.71       2.42
 344     3     Sort file               24     279.29    115.41       2.42
 341     4     vi: delete 2000 lines   24       4.25      1.75       2.43
 341     4     vi: delete 2000 lines   20       3.51      1.40       2.51
Table 1: Software-development results.


Figure 2 presents the performance ratios less the fastest and slowest 5 percent. Here the Pentium was never slower than the SPARC 5. Table 1 indicates that the Pentium was worse than the SPARC 5 on simple commands and better on more-complex commands, particularly sort.

Conclusions

Some of the tests in which the Pentium performed best and worst (compared with the SPARC) suggested that the Pentium was best at complex computation, and the SPARC 5 might have an advantage on simple operations that include I/O. There's no real surprise here - it is well known that architectures such as the Pentium are stronger in integer operations than in floating point, and that the opposite is true for the SPARCstation.


The authors are associated with Neal Nelson & Associates and can be contacted at 330 North Wabash Avenue, Chicago, IL 60611, or via e-mail at tom@nna.com.