Lethargic rpi3, but seemingly still running

[bob prohaska]

On Thu, Jul 18, 2019 at 11:20:51AM -0700, John-Mark Gurney wrote:
> bob prohaska wrote this message on Thu, Jul 18, 2019 at 08:18 -0700:
> > On Thu, Jul 18, 2019 at 10:58:11AM +0100, Jamie Landeg-Jones wrote:
> > > bob prohaska <fbsd at www.zefox.net> wrote:
> > > 
> > > > Every once in a while bsdtar will use a fraction of a percent of cpu, but
> > > > that seems to be all that's happening. The timestamp updates every other
> > > > second, typing echoes as expected but something like pwd takes twenty
> > > > seconds to answer. The controlling terminal for portmaster-devel has been
> > > > sitting at
> > > 
> > > What's your I/O like?
> > > 
> > > systat -v 1
> > > 
> > 
> > The machine got past the bottleneck and is running normally now, but
> > I'll try it the next time the machine bogs down. Does systat use a
> > different measurement method than top?
> 
> top doesn't like block device io...  iostat or systat -v 1 will do that.
> 

Here's a snippet of systat -v 1 output while un-tarring firefox files. 
%busy was close to zero, it looks like there's congestion or a deadlock
writing to the microSD card. At the time things like cd and ls were
very slow to respond (tens of seconds)

                                                       28 pdpgs       cpu2:ast
Disks mmcsd   da0 pass0                                   intrn       cpu3:ast
KB/t  12.00  0.00  0.00                            152904 wire      9 cpu0:preem
tps       5     0     0                             80072 act      51 cpu1:preem
MB/s   0.06  0.00  0.00                            671344 inact    80 cpu2:preem
%busy   213     0     0                               120   21104  27 cpu3:preem

Thanks for reading,

bob prohaska