I have reviewed blogpost from 2008 to date. I have Inherited a ruby on rails project for which I need to increase the test code.
I work on a laptop asus computer with an 8gen cpu i7U with 16gb ram and a 512gb ssd.
Initially I was running ubuntu 19.10, when I started the project and with about 1200 tests. it takes more than 1hr to run. Whereas on a 2015 macbook pro with 8gb of ram and an hdd, it takes only 2-3 min.
The log / test.log does not report errors, the tests do not hang, but waiting too long is not efficient, especially when i'll be increasing the number of tests.
So I Uninstall ubuntu, wipe off the ssd, install solus, arch and ubuntu, with the same setup for all through asdf as version manager and in no distro the time is less than 1hr.
Does anyone know why this happens in linux? The mac setup is also through asdf and it is fast enough.
Without knowing the specifics of the codebase or the tests, this question is equivalent to "how long is a piece of string."
There are many differences between linux and macOS. Cryptographic libraries may have different defaults. Memory limits for threads will be different. Memory limits for processors may be different.
Unless you can isolate specific tests which are wildly different and extrapolate from there, it's almost certainly going to come down to OS-level differences.
Related
I'm baffled. I have a VM running Ubuntu 14.04. I've followed procedures here: http://clang.llvm.org/docs/LibASTMatchersTutorial.html and am at the step to run ninja. This builds llvm and clang. Now, my VM is no slouch, I gave it 6GB of RAM and 4 CPUs and a 20GB swap file. The biggest problem comes at link time - it seems to start a large number of ld processes, each using at least 3-4GB or virtual memory, and at some point a lot of CPU each. But the the swap file grew to over 12GB and the processes are all IO bound, but I don't know if they are doing something useful, or thrashing. All I know is the disk is getting hammered and the jobs run forever. I've actually just dropped the CPU count to the VM to 1, to see if it might be more efficient with less parallelism, as I surmised the issue may be thrashing.
I suppose my disk could be slow... Any ideas? Should I be using make instead of ninja? My expertise is not Linux (although I'm getting there :-) ) So I'm following the tutorial but perhaps it is not recommended the "best" way to build the clang / llvm programs.
I have been there, It's happening with the latest svn release (but not if you get clang 3.8 or older releases). What is happening is that since during development a lot of debug information is also being generated for each compilation unit the file sizes are becoming big.
The solution is to turn off all the debug info that's been attached by default. You probably are not going to debug clang, so won't need it. SO instead of just doing this
cmake -G Ninja ../llvm -DLLVM_BUILD_TESTS=ON
What you should do is
cmake -G Ninja ../llvm -DLLVM_BUILD_TESTS=ON -DCMAKE_BUILD_TYPE=Release
All the other steps remain the same. Now I have not tested this with ninja, but have verified it with make on ubuntu (this tutorial, I modified the same thing in step 7). This should owkr as weel.
I'm evaluating PlasticSCM on a VMWare Machine with 4GB RAM and 4Core CPU. Since I've ported our trunk into the server (about 6GB of Data), the service ran out of memory (started swapping). I've increased the the VM RAM to 6GB This is actually more than I'd like to load the host system with, since I've also got VMs for PlasticSCM Client, TeamCity Server, TeamCity Agent.
I was trying to find a spec with details on hardware requirement for running PlasticSCM server which incorporates scaling. So far, I've only found the minimum requirement (512MB RAM etc.) and the system information of your heavy load and scale test. As far as I can see, it's all about RAM. :)
Anyway is there a detailed spec with recommendations for the hardware being used?
P.S.: Of course, in case of switching to Plastic we'd run the service on a real machine instead of VM.
From the beginning, I am a Windows master. I started with MS-DOS. I put up Windows 2.1 and every Windows since. I have 10 different Windows boxes running in my house right now, from Windows 7 Ultimate to varied flavors of Windows Servers. I haven't done Windows 8 and don't want to go there.
I have UNIX experience with both servers and varied software, but it hasn't been my preferred environment. However, I guess I am converting. I've tried to pretend to run UNIX under Windows using Cygwin and MSYS. My purpose is to build a development environment. Both have failed me. I have spent more time trying to fix a series of technical issues than I have developing. That is unacceptable.
My Ruby on Rails development environment is by far my highest current priority. I have websites to build, right now.
At this point, I have two options. One is to find a UNIX development environment in a cloud. The other is to convert one of my many machines to a true UNIX system. So, I need advice. I don't really want to build and babysit a system. The idea of a cloud-based development environment is very interesting, with the caveat that I don't chase it down another rat hole like I have with Cygwin and MSYS.
Here are the questions. Is there a solid cloud-based Ruby on Rails friendly development environment out there? Failing that, should I put up an Ubuntu-based system. If I go there, do I convert a workstation or a server?
Thanks...
I highly recommend Vagrant. I use this to do development on my Windows systems.
As you found out, Windows is terrible for RoR development. Your best option would be to use a VM like VirtualBox to run a Linux/Unix instance. There are other VM options, but VirtualBox is free.
Failing that, just convert once of your boxes to Linux/Unix. For development it does not matter one bit if it is a workstation or a server.
Mac OSX
The unofficial standard for RoR production is Linux, but for development it is Mac OSX. There has been a big migration of developers to the Apple platform that has been going on for many years now.
It gives you the best of both worlds: it is Unix underneath but it's also a commercial platform, a polished UI, and an available software ecosystem.
Yes, it's expensive, but people should ask themselves, why are people willing to pay so much? If you can afford 10 boxes for Windows, how about finding $ for one Mac? Then, you will have not just a workable RoR environment, but the best.
Or go VM
But if you don't take that advice, you may want to install a Hypervisor like Xen or XenServer for free, and then you can run both Windows and Linux on the same machine. This is slightly different than running a VM under Windows.
Externally, I have received a recommendation for EngineYard.com as an outstanding RoR environment and will ultimately consider it as my primary development/migration/production environment.
I have a working Debian system now and am building it out as a local RoR environment. It just seems to be right for a serious RoR development environment. I will go there as soon as it is fully built out because RoR is just meant for UNIX.
However, at least temporarily, I have found that RubyStack is a seriously usable Windows RoR development environment. It is 100% usable as a standalone system that doesn't require UNIX-style environments shoehorned onto Windows. Trying to run UNIX on Windows was a constant source of frustration, so this meets my immediate needs.
I'm just starting to learn Grails and Groovy. Did a fresh install of Grails 1.3.8 today and it crawls - I must have something in my environment causing a problem. I ran create-app (following a tutorial), then run-app. Both took quite a while but hey, first time thru. Ran run-app again, took almost 5 minutes, apparently int eh compiling phase. Windows 7 machine with 4 GB memory, Intel i5 CPU. Don't know where to start looking, but know this isn't normal.
When I've run into this normally I'm out of heap or permGen space. Fire up visualvm and check both of those memory limits. It'll slowdown considerably before crashing if your memory limits are too small
I wonder how it happens for you. I have 2gb ram and I run Ubuntu on pc and it's so fast. First check your memory limits.
And for your question, you can find a good disscussion over here.
I am studying the boot process in Linux. I am looking through this html page http://www.tldp.org/HOWTO/Bootdisk-HOWTO/x88.html. The first line under the section 3.1 "The boot process" says that "All PC systems start the boot process by executing code in ROM (specifically, the BIOS)".
My doubts are
Who loads the code in BIOS ?
Where is this code in BIOS located ?
To where is the code in BIOS loaded and executed ?
Kindly tell me references where i can get more information
Thanks,
LinuxPenseur
The code is already there in memory when the computer is powered on. It is in non volatile memory, meaning it doesn't disappear when the computer is turned off.
So the code is already there in a specific memory address, and the processor starts by running it.
More info here
A good question! Actually you do not need to reformat the HDD or even reinstall the OS on it unless the new PC is unable to run the existing OS on the drive.
Commonly, if you did a simple install of a Linux distribution, you would have no trouble moving the HDD to a new system and just running it. But if the OS is a version of Windows, the chances of this being the case are nearly zero: hardware vendors nearly always tune their device drivers for Windows so you cannot even use the same driver for two versions of Windows on the same machine (upgrading from XP to Windows 7 for example, often requires that you redownload at least a few hardware drivers).
And the problem often arises even with Linux if you have installed any high performance drivers. Sometimes you can perform a "recovery boot" from GRUB or LILO and get into a text mode screen with internet access, though. And if you can do that, often you can install the drivers for the new PC on the Linux HDD without doing a complete reinstall of Linux.
In fact, this is actually what that install CD or DVD is actually doing. It boots to a very vanilla flavor of the OS (Windows or Linux), then installs drivers for the hardware it detects, reboots (hopefully with functioning drivers) and wraps up the install process.