ssh sessions close spontaneously on rpi2

[Mark Millard]

On 2017-Nov-20, at 8:58 AM, bob prohaska <fbsd at www.zefox.net> wrote:

> Can anybody reproduce the following behavior on RPI2 ?
> 
> Boot the machine multi-user and start two ssh login sessions.
> 
> On one, start a top session, as a placeholder. On the second,
> su to root, cd to /usr/ports and run
> make -j8 clean > clean.log &
> 
> Next, try to open another (this makes three) ssh connection. Log in,
> and just watch. 
> 
> On my test box at FreeBSD 12.0-CURRENT (RPI2) #10 r325987 the connection
> fails within a couple of minutes; the login session terminates without
> explanation and the connection closes. 
> 
> No errors are on the serial console, /var/log/messages records nothing
> related. Ssh sessions started prior to starting make clean seem unaffected.

Given the messages that I've been getting but you have not,
I figure my attempting this under my current conditions
would not be effective.

But I've another oddity that you might try:

A) I booted and ran top on the serial console ( top -CaePosize )
B) I logged in 4 ssh sessions and had each do "openssl speed"

top gets an unexpected result: CPU 2 shows as 100% idle and the
others 0.0% idle.

The process CPU column agrees, in that that the total is
around 300% instead of around 400%. A couple of the
tend to show closer to 50% as long as 4 are running.
At 3 running it goes back to each being near 100%.

# uname -apKU
FreeBSD rpi2 12.0-CURRENT FreeBSD 12.0-CURRENT  r325700M  arm armv7 1200053 1200053

(I normally run a non-debug kernel that has debug symbols.)

I may try jumping to -r325997 .

===
Mark Millard
markmi at dsl-only.net