I was just starting to like the system…
It doesn’t completely freeze - it responds to mouse movements every 30 seconds or so; cursor disappears and returns in new location. Also it responded to ssh request by asking for password but then timed out. 
Hi, can you provide info:
Which PiDrive model?
What R-Pi model?
What is running (on the screen) when the system is in this funky state?
Are you running Foundation Edition software preloaded on the included sdcard? Were you able to get through the software installation process
What OS are you running (I assume Raspbian PIXEL)?
What type of 5V adapter and USB power cable are you using?
What USB devices are plugged in?
Are you using Ethernet?
I assume you’re using an HDMI monitor and no speakers or RPi camera attached to your Pi.
Thanks.
PiDrive model: WD3750LMCW
RasPi model: 3B
on screen: Sonic Pi, but in stopped mode (not running any program within)
preloaded software straight from the SD card. Installation ran OK.
Raspbian PIXEL.
5V adapter and power cable: those supplied with the unit
USB devices: those supplied - the hard drive and the mouse/keyboard receiver
using the built-in WiFi, no Ethernet cable
HDMI monitor
yes - speakers plugged in
Thanks for response!
cbm
Thanks, and thanks for being our customer on the PiDrive Compute Centre!
Thinking back through your description, you said 3Hz HDD LED flashing and my brain was thinking the reciprocal (every 3 seconds: 0.33Hz), which is why I was going down the path of system powering. 3x/sec is most likely drive formatting. When the software is installed, new partitions are set up and formatting is set up using ext4 “lazy init” mode. This establishes enough formatting to mount the device and get going, but the rest of the formatting is done in the background after the partition is mounted. So when you launch Raspbian for the first time, the disk LED will start flashing. If Raspbian were the only OS installed, it would be installed with the partition expanded to fill the drive and in this case the background formatting would take quite a while on a 375GB drive (like 1/2 hour or more). If the system is powered off before the formatting is completed, it’ll just start back up next time that OS/partition is launched. During the formatting process, the activity does impact system behavior and it’s possible it could cause mouse response hesitation/funkiness. Does this sound like what you might possibly be observing? If so, can you try launching Raspbian PIXEL and let the system sit until the disk LED stops the 3Hz flashing, then recheck mouse response?
If you’d installed many/most of the OS install items during set-up, the Raspbian PIXEL partition would be smaller and the time to complete formatting would be shorter.
I just did a web search on ext4 lazy init and this thread describes it pretty well:
http://www.hecticgeek.com/2015/01/ext4-external-hard-disk-busy-at-idle-fix/
Let me know if this is on the right track.
Thanks!
Sounds pretty good. I’ve left the system on all day today and it’s still
responding normally. I’m pretty sure I’d left the system on for several
hours each time it exhibited the problem. But I’ll give it some time and
some more experimentation. Today I did not start up Sonic Pi. Tonight I
will and let it sit overnight and see if everything’s still good in the
morning.
Thanks again!
cbm
It’s the morning and everything’s still good. I’m buying your
explanation. I think the expansion was taking way more than 1/2 hour,
though. I’m guessing more like 6 hours, based on the two events I
experienced.
I’d say we can call this issue closed. Thanks for your attention! You
can call me a fan.
cbm
Good to hear it seems to be working- thanks for the update. I was somewhat guessing at the 1/2 hour. Almost all of my work involves installing several or all OS items, so the Raspbian partition is usually not the whole drive and doesn’t take a really long time to complete the background formatting. I’ll try to set up a 375 with Raspbian-only install and see if I can replicate your experience.
Thanks.
