Retrochallenge 2009
      Mark Wickens
      13-Jan-2009 17:16
                                         Performance

      The VAXstation 4000/90 has the following specification (from the NetBSD VAX
      hardware reference[1]):

      Nickname: Cougar
      CPU: KA49-A, NVAX 72MHz (14ns), 10KB on chip cache, 256KB external cache
      VUP: 40         Specmark89: 32.8        Tps: 125
      Bus: Turbochannel, SCSI                 Enclosure: BA46-B

      VUP is a measure of the performance of the VAX compared with the VAX 11/780. It
      equates to roughly 0.5 MIPS (note that MIPS - millions of instructions per
      second is not a good indication of system performance).

      I thought I'd do a comparison between my IBM X60 laptop and the VAXstation
      4000/90 to see what the performance gap was and compare specifications.

                      IBM X60         VS4000/90       Ratio

      Memory          2048 MB         80 MB           26 x    
      Processor       1830 MHz*       72 MHz          25 x
      Disk Size       320 GB          (2+8) GB        32 x
      Disk Speed      100 MB/sec      5 MB/sec        20 x
      Level 1 Cache   64 KB           10 KB           6.4 x
      Level 2 Cache   2048 KB         256 KB          8 x

      *Intel Core Duo T2400 (Yonah, 65nm)

      In order to get a relative performance comparison with something real-world I
      decided to compile the image display/manipulation program xv. The program
      is bundled with a JPEG library and a TIFF library. It was compiled with default
      settings on the IBM X60 laptop running SuSE 10.3 linux and with the default
      settings on the VAXstation 4000/90:

                      IBM X60         VS4000/90       Ratio

      Compile Time    37 secs         950 secs        26 x

      I looked for other possible performance indicators, including benchmarks, but
      all the programs I looked at I could only get to compile under either OpenVMS or
      Linux not both.

      As far as my test goes, I'm a developer so this kind of performance interests
      me. It is a good test of complete system performance, with the exception of
      floating point performance.

      I could speculate that given the processor clock speed, memory capacity and disk
      transfer rate ratios that if you built a VAX with a 1.83 GHz clock, furnished it
      with 2 GB of RAM and used modern hard disks you would get approximately the same
      performance as the X60.

      Clearly, comparing a high-end VAX with a rather modest laptop is a little
      simplistic - but then, the Core Duo is a very powerful processor and is
      significantly faster than its' predecessor the mobile P4.

      So, a modern laptop is about 25 x quicker than a 1991 VAX.

      
      ENDNOTES

      1. NetBSD VAX Hardware Reference