Dear managers:
Here is an update of the situation with regard to my problems with the
network interface on my alphastation 200 4/166.
After more careful testing, it seems that my alpha (which has the new PCI
bus and the TULIP interface) does not have any problems dealing with our
group's DECstation 5000, and that the problems are not restricted to
NFS when dealing with the DECstation 3100 we have (There appear to be no
problems between the 3100 and 5000). Here are some more symptoms:
(1) frequent timeouts when issuing "ls" on a large directory mounted via NFS
from the 3100. No such problem when doing this on a file system mounted from
the 5000.
(2) many timeouts, delays and abortions when trying to copy a large
file (> 500 kbytes) in a directory NFS-mounted from 3100. NO problems
copying an equally large file from a volume mounted from the 5000.
(3) ftping a file from the 3100 resulted in a throughput of 5 kbytes/s.
FTPing the same file from the 5000 resulted in a throughput of better
than 20 kbytes/s. Note that for both tests, the file physically resided
on a disk attached to the 3100, which is NFS-mounted by the 5000. SO that
in the latter test, the 5000 has to first read the file via NFS from the
3100 before passing it onto the alpha.
(4) ping'ing the 3100 from the alpha resulted in about 1.3-1.4% of lost
packets over one hour. Similar test on 5000 resulted in NO loss at all.
Also no loss is seen when the 5000 pings the 3100. Losses were also seen
when ping'ing some of the other slower machines around from the alpha.
I thus come relunctantly to a hypothesis:
The 3100 cannot keep up with this alpha (which has better I/O performance
than most of the older alpha models...even ones nominally faster in CPU
power)...and a small percentage of packets are dropped....resulting in
confusion especially when makeing large volume transfers...
So...here is the question: If the above hypothesis is correct...can the
ethernet interface on the new alphastations (TU driver) be slowed down
to match the other workstations on the network?
thanks
Charlie Jui
Received on Wed Feb 01 1995 - 20:31:42 NZDT