So, I've been given a piece of software, originally written on a regular ol' laptop (running Ubuntu), and asked to see if I can get it running on a Raspberry Pi.
I've installed the software (and configured it) on two seemingly-identical Raspberry Pis running the same version of Ubuntu Mate 16.04. I've done the whole update/upgrade schtick on both multiple times.
The version of the software on each of the two Pis is the same, copied from the same flash drive, run on the same directory and with the same input parameters. They're both Pi model 2b, armV7r4, etc.
On one of them, the code runs properly, produces the expected output, and finishes up in about 2-minutes-twenty.
On the other, the code inevitably segfaults after about a minute twenty.
The code also compiles without issue on each.
The only apparent hardware difference I could spot between the two Pis is that one processor runs at about twice the BogoMIPS speed as the other one.
Can anyone suggest some likely comparisons I could make between the two devices to see if I can figure out what's causing it to miraculously work on one and not on the other?
It appears the issue I was working on was caused by residual, inaccessible files left over from a previous user I thought I'd thoroughly removed from the device.
When my software encountered them, it threw a fit and died.
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Scenario: I'm logging in remotely to my M1 Mini, and trying to run a Perl script which launches a long stream of instances of my (compiled for arm64 C++) program, one at a time, for testing purposes. Because it will surely take hours to run the full sequence, I nohup the Perl script.
I launched the first test run about 36 hours ago, and it is about one-third completed thus far. This is much slower than I'd expected -- in general my individual tests of the program have shown this machine to be faster than any other machine I have, and this isn't living up to that at all.
I got to thinking about this, and wondered if my code is getting treated as a "background" task, and run on one of the power-efficient "Icestorm" cores rather than one of the fast "Firestorm" cores. Does anyone know how to detect which core a process is running on and/or control which core a process is run on?
I tried to run a small program with arrays in C in my laptop (in Codeblocks) and it was supposed to return an error (or at least that was what I was waiting to see). But it run crazy couldn't stop it an since then my laptop functions but the screen is a mess. It is flickering in a certain part all the time and views of open windows stick forever and it goes worse as time goes by. I run diagnostics but there is no problem located. I formatted it and still the same. Is this hardware problem?
I am working on Laravel with docker.
If I run php unit test in mac os, it takes few seconds.
However on windows 10, it takes few mins.
Is there anyway to fix this problem?
Thanks.
If you're running on a non-Linux OS, Docker has to virtualise your file system, and this requires a certain amount of time per file. For programs that are compiled into one executable, this is less of a problem at runtime (but clearly with its own compilation-time implications), but for scripting languages like PHP this can mean that every request runs super slowly, since every file that is used has to be 'translated' every time it is read. This is also a problem on Docker for Mac (so you're actually experiencing problems there, too, but less so, since at least it's a Linux system under the hood.) Linux is, I believe, completely virtualised on Windows which is going to add even more time.
This Reddit discusses the problem to an extent:
https://www.reddit.com/r/docker/comments/7xvlye/docker_for_macwindows_performances_vs_linux/
With this being particularly interesting (I have not tried it myself):
https://nickjanetakis.com/blog/setting-up-docker-for-windows-and-wsl-to-work-flawlessly
There is also a good community-created solution which we have used to solve our Docker for Mac problem. I don't see why their Windows options wouldn't work similarly well in your case. You can find it here:
https://github.com/EugenMayer/docker-sync/wiki/docker-sync-on-Windows
It basically sets up an intermediate service that copies all the files over into an intermediate volume (that uses the 'correct' filesystem) only when the file is updated, therefore speeding up run speed immensely.
I know it looks like quite an intimidating process, but this problem is fundamental, so you're going to have to do a certain amount of work to fix things!
FWIW I had that working on Docker 4 Mac, but it added a layer of complexity to our dev process that I found annoying, so in the end I've got myself a Linux box for work. To be honest, installing Linux as dual boot on my Windows machine (which has been my at-home solution) was probably easier than tweaking Docker 4 Mac to my satisfaction, so you might want to consider that. I have used this page twice:
https://itsfoss.com/install-ubuntu-1404-dual-boot-mode-windows-8-81-uefi/
And it's worked fine each time. One caveat - it suggests a low amount of disk for your root (/) volume, but Docker gets mounted on root so give it around 100G (not the 10-20G that page recommends.)
Since some years ago I started using Qt in both Windows 7 as well as in Linux Ubuntu and it would always compile fast with MinGW being used for Windows. But in the last couple of years or so, maybe thanks to updates in the version of both Qt and MinGW, I started detecting a slow down in the compiling speed inside Windows. I did some research trying to find why MinGW had started to become so slow compared to Linux (it wasn't before!) and everything people told me was that MinGW was slower in Windows and that it would be better, if possible, to just use Linux.
Since I wanted to continue my project, I followed the suggestion and since I've being using Linux with relatively no problems. The situation now is that I must go back to Windows (now updated to Windows 10) to make visual corrections for this OS and I need to once again work with MinGW having to face the same problem as before.
But for some reason it seems that the slowness of MinGW became even worse! While before I at least was able to compile the app in around 4 minutes, now the last time I tried it took 38 minutes before I gave up and went to sleep - and this is for a project that takes only 1:03 minute to be compiled in Linux [under the same compile configuration]!
Well I'm still aware about the slowness of MinGW, but as a quick research around this problem on the web reveals, that is just too slow: all backtesting one can find in other threads here on SO reveals at best 2x-3x more time to compile a project, not 38x+!!
So I would like to know what kind of possible problems I might have in my Windows for this exaggerated slowness to happen. I know I ended up installing at least 4 different versions of MinGW; could this have brought the problem?
It's interesting also to notice that when compiling using the -j option and watching the Compile Output log in Qt Creator alongside Process Explorer, there are moments when the compiling simple pauses for 10 seconds or more and the CPU usage drops from its ~100% to close to 5% with nothing happening till it suddenly continues the compilation process. I'm sure this constant pauses are part of the above average time, but I have no idea why MinGW is showing this behaviour.
You might want to check where the time is spent.
There a lot of tools that allow you to capture what a certain process is doing, I name just two of them:
ProcMon
XPerf or its successor
But to analyze the reports generated by these tools you need a rather deep understanding. If this doesn't help temporarily disable other running services and program step-by-step (if you want to know which program causes the problem) or disable all of them at once.
Looking at the spikes of cpu usage that TaskManager or Procexp by sysinternals show might help too to identify those components that block your cpu.
If your antivirus is the cause of the collision that makes the compile so slow you can define exceptions, then the antivirus will not scan certain programs or paths.
So perhaps it is easier to first try the compilation process with a disabled antivirus software or even from a clean live boot Windows CD.
I'm having a very strange problem. I'm using dfs-datastores Pail abstraction to write data to HDFS in Java. I don't think the Pail piece is important to the problem though.
When it calls org.apache.hadoop.fs.FileSystem getFS(java.lang.String path) with a path on my local filesystem it pauses for about 2 minutes seemingly doing nothing then returns. This is on my laptop.
The weird thing is that it worked really fast when I was on the network at my office today, but now that I'm home it's doing it again. I'm running Ubuntu 10.10 64-bit with Java 1.7.
Anyone have any ideas what it's doing? What could be different between being at work and being at home?
UPDATE:
I've been stepping through code with the debugger and it seems to be having trouble in Configuration.loadResource(). It's calling that multiple times and it will take 5-10 seconds to return from that function.
UPDATE2:
I've narrowed this down a little further. The biggest hang up seems to be when it calls KerberosName.setConfiguration(). Which would explain why it runs fast at work since the Active Directory acts as a Kerberos server. I don't have one here at home, so it can't find one. Now they question is why in the world it's trying to load the Java Kerberos stuff.
I found a solution (or at least a work around). I installed the krb5-kdc package and now my little program runs fast without any unexplained pauses. After this I removed krb5-kdc, tested and it was still running fast. I removed /etc/krb5.conf and it started doing the pause again. It looks like using the Hadoop library on Ubuntu (at least) requires a /etc/krb5.conf file.
Maybe this will help someone else.