SGI Performance Comparisons

Archiving a single large file to DAT (DDS1 vs. DDS3)

Last Change: 08/May/2008

In this test, I timed how long the various systems took to archive the main 179685K (175.5MB) Quake2 pak0.pak data file to DAT. All tests were performed using IRIX 6.5. Data rates are in K/sec. The command sequence used to run the test, which was entered in a raw xterm, was:

   timex tar cv pak0.pak

Table 23 shows the results for archiving the pak0.pak file. The DDS1 column is not yet complete, mainly due to lack of time.

                        DDS1 Python      DDS1 Python      DDS3 Sony
                       25601-XXX2.75    28388-XXX5.AC      SDT9000
                        time / rate      time / rate     time / rate

O2 R5000SC/200:                          8:26 / 355      2:00 / 1497    [hinv]
Indigo2 R4400SC/250:   16:48 /  178                      2:07 / 1415
Indy R4400SC/200:                                        2:11 / 1372
Indy R4600PC/133:                                        3:23 /  885
Indy R4600PC/100:                                        3:14 /  926

   Table 23: DDS1 vs. DDS3 DAT performance for
             archiving a large file to DAT.

Just as with the CDROM tests, slower CPUs cannot fully exploit a fast DAT drive.

One might also expect the DDS3 results to show something similar to CDROM TEST 2, ie. transfer rate depends on raw clock speed. However, the figures are somewhat more even for archiving a large file to DAT. This could be because the DAT drive often takes some time to begin and end the archiving operation, but could also be because of architectural differences in I/O systems..

Note that I also have a DDS4 I could test, but I can't say when I'd be able to do this.