@crashtech:
It looks like you have three "good" hosts with Mint 19.3 and boinc version 7.9.3,
and two "bad" hosts with Mint 19.3 and boinc version 7.17.0.
Right?

(On the other hand, when I look at wingmen of my own results, there are circa two hosts which are persistently spamming the project recently with bogus few-seconds results, and these two hosts have Mint 19.3 and boinc version 7.9.3. Their owner is anonymous, hence we have no way to wake up the pilot.)

@crashtech, in addition to ProtectSystem=full, you could try: PrivateTmp=false

@crashtech, "df" reports "file system disk space usage", i.e. the used space and available space in the filesystem in which the optionally given file or directory resides. My main intention was to verify how much free space is left in your /tmp. We now know that there is plenty of space left in it. (There are 180 GBytes available in /tmp.)

As for the boinc-client.service unit file: Compared with the boinc-client.service file on my computers, yours has several extra lines. The following four, explained in "man systemd.exec", stick out to me:

ProtectHome=true

Most likely harmless to the NWChem (...long) application.

PrivateTmp=true

In theory this should be OK for NWChem long.

ProtectSystem=strict

This is probably the culprit! As I understand the documentation, this will make /tmp read-only.
Either relax this from strict to full, or append

-/tmp

to the ReadWritePaths line.
Then restart the boinc-client service. Or maybe you even need to reboot, I don't know.
Then fetch one QuChemPedIA task and see if it runs normally.

ProtectControlGroups=true

In theory this should be OK.

(Documentation of the systemd service file format is spread over "man systemd.unit", "man systemd.service", and "man systemd.exec".)

crashtech wrote:

Has there been a resolution to this issue? One of my computers only runs WUs for a few seconds, then marks them as complete

https://quchempedia.univ-angers.fr/athome/results.php?hostid=1227

@crashtech, maybe this host has a full /tmp (like Alien Seeker suspected with the own host). Check with "df -h /tmp" for example.

ga7pxsl@GAX570UD_test:~$ df -h /tmp
Filesystem      Size  Used Avail Use% Mounted on
/dev/sda5       228G   37G  180G  17% /
ga7pxsl@GAX570UD_test:~$ df -h /home/ga7pxsl
Filesystem      Size  Used Avail Use% Mounted on
/dev/sda5       228G   37G  180G  17% /
ga7pxsl@GAX570UD_test:~$ df -h /
Filesystem      Size  Used Avail Use% Mounted on
/dev/sda5       228G   37G  180G  17% /

ga7pxsl@GAX570UD_test:~$ df -h
Filesystem      Size  Used Avail Use% Mounted on
udev             16G     0   16G   0% /dev
tmpfs           3.2G  2.0M  3.2G   1% /run
/dev/sda5       228G   37G  180G  17% /
tmpfs            16G  208K   16G   1% /dev/shm
tmpfs           5.0M  4.0K  5.0M   1% /run/lock
tmpfs            16G     0   16G   0% /sys/fs/cgroup
/dev/sda1       511M  6.1M  505M   2% /boot/efi
tmpfs           3.2G   32K  3.2G   1% /run/user/1000

Or the boinc-client service on this host is set up in a way which does not permit it to create files outside of its data directory, or at least not in /tmp. What does /lib/systemd/system/boinc-client.service contain on this host?

[Unit]
Description=Berkeley Open Infrastructure Network Computing Client
Documentation=man:boinc(1)
After=network-online.target

[Service]
Type=simple
ProtectHome=true
PrivateTmp=true
ProtectSystem=strict
ProtectControlGroups=true
ReadWritePaths=-/var/lib/boinc -/etc/boinc-client
Nice=10
User=boinc
WorkingDirectory=/var/lib/boinc
ExecStart=/usr/bin/boinc
ExecStop=/usr/bin/boinccmd --quit
ExecReload=/usr/bin/boinccmd --read_cc_config
ExecStopPost=/bin/rm -f lockfile
IOSchedulingClass=idle
# The following options prevent setuid root as they imply NoNewPrivileges=true
# Since Atlas requires setuid root, they break Atlas
# In order to improve security, if you're not using Atlas,
# Add these options to the [Service] section of an override file using
# sudo systemctl edit boinc-client.service
#NoNewPrivileges=true
#ProtectKernelModules=true
#ProtectKernelTunables=true
#RestrictRealtime=true
#RestrictAddressFamilies=AF_INET AF_INET6 AF_UNIX
#RestrictNamespaces=true
#PrivateUsers=true
#CapabilityBoundingSet=
#MemoryDenyWriteExecute=true

[Install]
WantedBy=multi-user.target

Possibly there is a problem with the BOINC installation itself.
It would probably be easier just to upgrade to the latest version, which you can do with this PPA:

sudo add-apt-repository ppa:costamagnagianfranco/boinc
sudo apt-get update

https://launchpad.net/~costamagnagianfranco/+archive/ubuntu/boinc

Mon 15 Jun 2020 08:42:37 AM MDT |  | Starting BOINC client version 7.17.0 for x86_64-pc-linux-gnu

Very strange. I don't see anything wrong with your machines.
Maybe memory? Overclocking? It must be something different about that one.

Sometimes files get corrupted though. I would detach from the project, and then re-attach.

I run all of my work units as t1, by setting "Max # CPUs 1" in the preferences.

I have never seen the problem of the short runs that I can remember.
https://quchempedia.univ-angers.fr/athome/results.php?hostid=2356