Re: CURRENT slow and shaky network stability

Am Sat, 26 Mar 2016 14:26:45 -0700 (PDT)
Don Lewis <truckman_at_FreeBSD.org> schrieb:

> On 26 Mar, Michael Butler wrote:
> > -current is not great for interactive use at all. The strategy of
> > pre-emptively dropping idle processes to swap is hurting .. big time.
> > 
> > Compare inactive memory to swap in this example ..
> > 
> > 110 processes: 1 running, 108 sleeping, 1 zombie
> > CPU:  1.2% user,  0.0% nice,  4.3% system,  0.0% interrupt, 94.5% idle
> > Mem: 474M Active, 1609M Inact, 764M Wired, 281M Buf, 119M Free
> > Swap: 4096M Total, 917M Used, 3178M Free, 22% Inuse
> > 
> >   PID USERNAME       THR PRI NICE   SIZE    RES STATE   C   TIME    WCPU
> > COMMAND
> >  1819 imb              1  28    0   213M 11284K select  1 147:44   5.97%
> > gkrellm
> > 59238 imb             43  20    0   980M   424M select  0  10:07   1.92%
> > firefox
> > 
> >  .. it shouldn't start randomly swapping out processes because they're
> > used infrequently when there's more than enough RAM to spare ..  
> 
> I don't know what changed, and probably something can use some tweaking,
> but paging out idle processes isn't always the wrong thing to do.  For
> instance if I'm using poudriere to build a bunch of packages and its
> heavy use of tmpfs is pushing the machine into many GB of swap usage, I
> don't want interactive use like:
> 	vi foo.c
> 	cc foo.c
> 	vi foo.c
> to suffer because vi and cc have to be read in from a busy hard drive
> each time while unused console getty and idle sshd processes in a bunch
> of jails are still hanging on to memory even though they haven't
> executed any instructions since shortly after the machine was booted
> weeks ago.
> 
> > It also shows up when trying to reboot .. on all of my gear, 90 seconds
> > of "fail-safe" time-out is no longer enough when a good proportion of
> > daemons have been dropped onto swap and must be brought back in to flush
> > their data segments :-(  
> 
> That's a different and known problem.  See:
> <https://svnweb.freebsd.org/base/releng/10.3/bin/csh/config_p.h?revision=297204&view=markup>

CURRENT has rendered unusable and faulty. Updating ports for poudriere ends up in this
error/broken pipe from remote console:

 [~] poudriere ports -u -p head
[00:00:00] ====>> Updating portstree "head"
[00:00:00] ====>> Updating the ports tree... done
root_at_gate [~] Fssh_packet_write_wait: Connection to 192.168.250.111 port 22: Broken pipe


Although not under load, several processes over time gets idled/paged out - and they
never recover, the connection is then sabott, the whole thing unusable :-(