Re: Performance degradation over time on VAX...

[Ken Wellsch <kcwellsch%outlook.com@localhost>]

After seeing Jason's posting, I wanted to continue with my amateur sniffing effort.

On a VAXstation 4000/60 (as I used before) using an emulation SCSI card
(as before) I've run through a whole lot of official release ISO's.

This time I installed each release and ran the following two command
sequences (based on my interpretation of Jason's work).

ntpdate -u pool.ntp.org ; dd if=/dev/zero  of=/dev/null bs=4096 count=100000 ; ntpdate -u pool.ntp.org
ntpdate -u pool.ntp.org ; dd if=/dev/rsd0c of=/dev/null bs=4096 count=30000 ; ntpdate -u pool.ntp.org

I selected count values, as before, so they would give me more than 60 seconds of runtime.

I liked the fact that the dev/zero case bypasses any complex device driver and "real" device.

The ntpdate portion came from Google helping me get a working command for the older releases.

Hopefully these time corrections will show no gross time issues during the brief runtime.

============================================================
---- dd if=/dev/zero  of=/dev/null bs=4096 count=100000 ----
============================================================

2.0.0   409.60 MB in  92.476 secs (4.43 MB/s)   offset 0.014478 sec
2.0.2   409.60 MB in  81.469 secs (5.03 MB/s)   offset -0.017075 sec
2.1.0   409.60 MB in  81.851 secs (5.00 MB/s)   offset -0.010569 sec
3.0.0   409.60 MB in  95.097 secs (4.31 MB/s)   offset 0.017103 sec
3.0.2   409.60 MB in  82.617 secs (4.96 MB/s)   offset -0.020239 sec
3.1.1   409.60 MB in  81.218 secs (5.04 MB/s)   offset -0.002095 sec
4.0.0   409.60 MB in  82.683 secs (4.95 MB/s)   offset 0.000865 sec
4.0.1   409.60 MB in  80.682 secs (5.08 MB/s)   offset -0.002540 sec
5.0.0   409.60 MB in  73.896 secs (5.54 MB/s)   offset -0.006272 sec
5.0.2   409.60 MB in  73.251 secs (5.59 MB/s)   offset -0.007861 sec
5.1.2   409.60 MB in  74.305 secs (5.51 MB/s)   offset 0.002074 sec
5.1.5   409.60 MB in  77.247 secs (5.30 MB/s)   offset -0.002412 sec
5.2.3   409.60 MB in  74.234 secs (5.52 MB/s)   offset 0.007559 sec
6.0.0   409.60 MB in 131.145 secs (3.12 MB/s)   offset -0.008218 sec
6.0.6   409.60 MB in 145.589 secs (2.81 MB/s)   offset 0.008178 sec
6.1.3   409.60 MB in 126.978 secs (3.23 MB/s)   offset -0.013498 sec
7.0.0   409.60 MB in 128.069 secs (3.20 MB/s)   offset 0.162509 sec
7.1.2   409.60 MB in 130.681 secs (3.13 MB/s)   offset 0.886323 sec
7.2.0   409.60 MB in 130.732 secs (3.13 MB/s)   offset 0.094225 sec
8.0.0   409.60 MB in 122.039 secs (3.36 MB/s)   offset 0.969403 sec
8.1.0   409.60 MB in 122.904 secs (3.33 MB/s)   offset 0.209796 sec
8.2.0   409.60 MB in 118.316 secs (3.46 MB/s)   offset 0.834749 sec
9.0.0   409.60 MB in 115.717 secs (3.54 MB/s)   offset 0.657326 sec
9.1.0   409.60 MB in 120.125 secs (3.41 MB/s)   offset 0.359956 sec
9.2.0   409.60 MB in 126.775 secs (3.23 MB/s)   offset 0.434128 sec
9.3.0   409.60 MB in 117.573 secs (3.48 MB/s)   offset 0.408211 sec
10.0.0  409.60 MB in 130.912 secs (3.13 MB/s)   offset +0.305483 sec
10.1.0  409.60 MB in 132.401 secs (3.09 MB/s)   offset +0.021104 sec
11.rc5  409.60 MB in 142.258 secs (2.88 MB/s)   offset +0.071411 sec

===========================================================
---- dd if=/dev/rsd0c of=/dev/null bs=4096 count=30000 ----
===========================================================

2.0.0   122.88 MB in 104.826 secs (1.17 MB/s)   offset 0.006032 sec
2.0.2   122.88 MB in 103.624 secs (1.19 MB/s)   offset 0.012788 sec
2.1.0   122.88 MB in 105.223 secs (1.17 MB/s)   offset 0.008445 sec
3.0.0   122.88 MB in 101.946 secs (1.21 MB/s)   offset 0.006388 sec
3.0.2   122.88 MB in 103.549 secs (1.19 MB/s)   offset -0.010305 sec
3.1.1   122.88 MB in 103.051 secs (1.19 MB/s)   offset -0.255196 sec
4.0.0   122.88 MB in 111.208 secs (1.10 MB/s)   offset 0.000746 sec
4.0.1   122.88 MB in 111.860 secs (1.10 MB/s)   offset 0.001173 sec
5.0.0   122.88 MB in 131.359 secs (0.94 MB/s)   offset 0.001126 sec
5.0.2   122.88 MB in 131.080 secs (0.94 MB/s)   offset -0.004246 sec
5.1.2   122.88 MB in 132.431 secs (0.93 MB/s)   offset -0.000763 sec
5.1.5   122.88 MB in 134.746 secs (0.91 MB/s)   offset -0.000325 sec
5.2.3   122.88 MB in 128.433 secs (0.96 MB/s)   offset -0.013470 sec
6.0.0   122.88 MB in 150.388 secs (0.82 MB/s)   offset 0.005609 sec
6.0.6   122.88 MB in 155.608 secs (0.79 MB/s)   offset -0.005730 sec
6.1.3   122.88 MB in 153.486 secs (0.80 MB/s)   offset 0.004184 sec
7.0.0   122.88 MB in 157.764 secs (0.78 MB/s)   offset 0.173563 sec
7.1.2   122.88 MB in 157.760 secs (0.78 MB/s)   offset 0.224465 sec
7.2.0   122.88 MB in 156.500 secs (0.79 MB/s)   offset 0.099339 sec
8.0.0   122.88 MB in 162.346 secs (0.76 MB/s)   offset 0.070651 sec
8.1.0   122.88 MB in 159.242 secs (0.77 MB/s)   offset 0.221792 sec
8.2.0   122.88 MB in 159.596 secs (0.77 MB/s)   offset 0.229680 sec
9.0.0   122.88 MB in 164.284 secs (0.75 MB/s)   offset 0.613972 sec
9.1.0   122.88 MB in 166.545 secs (0.74 MB/s)   offset 0.379712 sec
9.2.0   122.88 MB in 163.019 secs (0.75 MB/s)   offset 0.438902 sec
9.3.0   122.88 MB in 163.831 secs (0.75 MB/s)   offset 0.413608 sec
10.0.0  122.88 MB in 181.440 secs (0.68 MB/s)   offset +0.190593 sec
10.1.0  122.88 MB in 180.109 secs (0.68 MB/s)   offset -0.015763 sec
11.rc5  122.88 MB in 181.721 secs (0.68 MB/s)   offset -0.007328 sec