Quad core Raspberry Pi crashes, Single core doesn't
21 Sep 2015 8:31:06 UTC
Topic 198240
(moderation:
I am running einstein@home on a Raspberry Pi 2B and a Raspberry Pi 1B (larger memory variant). (You can spare me the quips about a mouse trying to eat an elephant.) Both have been essentially dedicated to the task for months. The 2B dies every couple of weeks. The 1B chugs along without a hiccup.
Both Pis are powered from the same dual-outlet, 20W adaptor, and both are physically wired to my modem-router. Neither has a console or a keyboard - I SSH and/or VNC into both of them. The 2B has a Pi Noir plugged in and configured (tested and works), but not used.
Can I please have some hints about the diagnosis process I should follow?
Quad core Raspberry Pi crashes, Single core doesn't
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The Pi2's are much more fussy about the power supply. I was using a dual USB charger to run the B's and then B+ but the Pi2's kept crashing. I went back to my original USB power adapters and that solved most of my problems.
The other problem I found was that despite having heatsinks, when overclocked the Pi2's would crash every few days. Once I went back to stock speed they can run for months without any issues. If you are going to overclock then you need to use heatsinks and possibly a fan, they can get quite hot. Google "Pi Overclockers Kit" and see what takes your fancy however heatsinks are usually sufficient.
To narrow it down I would suggest you try both and run them for a while. If stable then try reapplying the overclock. If it fails at 1000Mhz then try a smaller increase, but for the sake of the extra hour or so you save on a work unit it's probably not worth the trouble.
I have three Pi2's and one B+ crunching. Not too sure why I bother with the B+ any more, I should replace it with another Pi2. All my Pi2's are running stock speed (700Mhz) with copper heatsinks. I cut a hole in the top of one Pi2 case and put a 60mm fan grill over it, but the other two are running topless. See my blog for pictures of the case mod.
BOINC blog
RE: Can I please have
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There are some specific things you can check:
1) Is the red LED blinking? Unlike with the PI1, the red LED on the PI2 is not supposed to blink. If it blinks this means that the voltage is dropping below the safe threshold ("brown out").
2) CPU temperature check: run
/opt/vc/bin/vcgencmd measure_temp
while all cores are under full load and the ambient temp. is not exceptionally low. Anything under 70 deg C is still perfect, anything over (say) 73 deg C is somewhat high and anything close to 80 deg C is absolutely too high.
Cheers
HB
Interesting you should
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Interesting you should mention the red LED. The 2B usually (invariably, I think) crashes with the red LED on solid.
Thanks for the hints. I have not been overclocking, but perhaps I should invest in some cooling anyway.
Nice to see some more Pis out there looking for Gravity Waves!
When you say dual outlet 20w,
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When you say dual outlet 20w, it isn't a Belkin one is it? That's what I used before the Pi2's. They are a USB charger and not a switch-mode power supply. You'll need a proper power supply rather than a charger for the Pi2. I got my power supplies (for the original B model) from element14. Then I started using the Belkin dual USB which worked fine with the B and the B+ but not with a Pi2 (nor a Parallella).
BOINC blog
RE: Nice to see some more
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To avoid misunderstandings: currently only the "Binary Radio Pulsar" search, which looks for unknown pulsars in radio telescope data, runs on the PI, not the GW searches. Pulsars are in general useful for the understanding of gravity and you can even 'build' detectors for GW with pulsars (so called Pulsar Timing Arrays), but the BRP search is not directly looking for gravitational waves.
Yes,ok ... helping with the
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Yes,ok ... helping with the search for gravity waves.
RE: When you say dual
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The brand is Cygnet. I suppose it would be described as a charger. Very neat little unit, but yeah ... now that you have asked, i'll look at it more closely.
Interesting point - somewhat
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Interesting point - somewhat off topic - but I can't find a primary reference for the default LED behaviours on the Raspberry Pi 2 - plenty for the Pi 1, but are they the same? The red LED on my Pi 2 is "off" all the time, which is opposite to the Pi 1.
RE: Interesting point -
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For the Pi2 it should be On - Constantly. If its off you haven't got enough juice. Check you power supply and its USB cable. There have been complaints in the Pi forums about cheap USB cables causing problems.
The green LED on the other hand indicates I/O activity to the SD card and will blink on when it does some and should be off at other times.
BOINC blog
Eeesh! All this time I have
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Eeesh! All this time I have been abusing my RPi 2B and not even realising it. Ah well, better late than never, I have ordered an officially sanctioned power supply which should make me see red. Thanks, all, for your input.