[Linux-decnet-user] FYI: linux-decnet performance

[Larry B. <ba...@us...>]

I ran some crude timing tests on our network to compare the speed of =
OpenVMS Backup using several combinations, including linux-decnet.

The reason I installed linux-decnet is because I bought 3 Maxtor 250 GB =
IDE disks and NFS exported them from a Red Hat 8.0 Linux box.  I =
expected to backup our Unix, Linux, NetApp NAS, and OpenVMS systems =
using NFS instead of tapes (we've had our fill of tapes).  =
Unfortunately, the NFS client implementation on our OpenVMS systems, =
Process Software MultiNet V4.4, supports only NFS version 2, not version =
3.  Version 2 limits the NFS file size to 2 GB, so full disk backups =
from OpenVMS to the NFS disks failed when the save sets hit 2 GB.  I'm =
hoping linux-decnet can get around this limitation until the MultiNet =
NFS client supports version 3.

I'm pretty satisfied with the performance of linux-decnet.  My test =
results are given below.

Larry Baker
US Geological Survey


I ran an OpenVMS BACKUP/VERIFY of my personal directory tree on our =
AlphaServer 100A 333 MHz with internal 7200 RPM SCSI disks and =
100-TX/FDX Ethernet.  My directory tree is just over 240 MB.  I did this =
during the middle of the day, not during any particularly quiet time.

Local disk-to-disk: SAMOA (333 MHz Alpha, 100-TX/FDX Ethernet) =
PUB:[BAKER...] (7200 RPM SCSI) to BAR:[BAKER]PUB.BCK (7200 RPM SCSI), =
~18 min.

Local disk-to-NFS disk: SAMOA PUB:[BAKER...] to WAVE:[BAKER]PUB.BCK =
(Network Appliance F720, Gigabit Fiber Ethernet, 10000 RPM Fiber =
Channel), ~5 min.

Local disk-to-DECnet disk: SAMOA PUB:[BAKER...] to BOREGO::PUB.BCK (233 =
MHz Alpha, 100-TX/FDX Ethernet, 7200 RPM SCSI), ~8 min.

Local disk-to-DECnet disk: SAMOA PUB:[BAKER...] to =
WAVLET::SYSDISK:[BACKUP.OPENVMS]BAKER.BCK (400 MHz PII RH8.0 Linux, =
100-TX/FDX Ethernet, 5400 RPM IDE), ~12 min.