Linux - Software This forum is for Software issues.
Having a problem installing a new program? Want to know which application is best for the job? Post your question in this forum. |
Notices |
Welcome to LinuxQuestions.org, a friendly and active Linux Community.
You are currently viewing LQ as a guest. By joining our community you will have the ability to post topics, receive our newsletter, use the advanced search, subscribe to threads and access many other special features. Registration is quick, simple and absolutely free. Join our community today!
Note that registered members see fewer ads, and ContentLink is completely disabled once you log in.
Are you new to LinuxQuestions.org? Visit the following links:
Site Howto |
Site FAQ |
Sitemap |
Register Now
If you have any problems with the registration process or your account login, please contact us. If you need to reset your password, click here.
Having a problem logging in? Please visit this page to clear all LQ-related cookies.
Get a virtual cloud desktop with the Linux distro that you want in less than five minutes with Shells! With over 10 pre-installed distros to choose from, the worry-free installation life is here! Whether you are a digital nomad or just looking for flexibility, Shells can put your Linux machine on the device that you want to use.
Exclusive for LQ members, get up to 45% off per month. Click here for more info.
|
|
07-19-2015, 07:00 PM
|
#1
|
Member
Registered: Apr 2014
Distribution: debian
Posts: 42
Rep:
|
Floatin point or fixed point in packaged binaries?
If I use
apache/nginx, cgi/php, etc..
samba, postfix/exim/sendmail...
on debian linux
I use floating point or fixed point in these softwares?
I mean in the above "standard" programs ( not in the php scripts or in any other user programs ).
Debian's packages are still 386 compatibles. Is this decided by the gcc (or other compiler) when the package maintainer compiles the program?
Is it an architectural question? Will the program works differently for example on a sparc and on an 64bit xeon? Or the program's source determines the usage of the FPU?
Is there a debugger/audit subsystem/source analyser to get the fpu usage of a program?
|
|
|
07-20-2015, 01:31 AM
|
#2
|
Senior Member
Registered: Oct 2005
Location: Horgau, Germany
Distribution: Manjaro KDE, Win 10
Posts: 2,199
Rep:
|
Debugger: http://www.drdobbs.com/testing/13-li...ewed/240156817
You can also analyze the source code of these programs. (filetype float). Just download these packages from the appropriate pages ( http://httpd.apache.org/ , https://www.samba.org/ , ...)
And the FPU does not always use floating point.
Try to install Gentoo and activate FPU.
Last edited by Keruskerfuerst; 07-20-2015 at 07:24 AM.
|
|
|
07-20-2015, 07:34 AM
|
#3
|
LQ Guru
Registered: Feb 2004
Location: SE Tennessee, USA
Distribution: Gentoo, LFS
Posts: 10,881
|
Huh?
All implementations of the 386 architecture today include a built-in FPU which is used for all floating-point operations. The CPU also has a decimal mode. If it is a 32-bit program, the CPU will operate in 32-bit compatibility mode if it is a 64-bit unit.
Last edited by sundialsvcs; 07-20-2015 at 07:35 AM.
|
|
|
07-20-2015, 08:54 AM
|
#4
|
Member
Registered: Apr 2014
Distribution: debian
Posts: 42
Original Poster
Rep:
|
yes, "386 architecture" or x86 has builtin fpu nowadays, but what about sparc T1 many cores, but only one fpu, or my dns 313 nas ( Processor : FA526id(wb) rev 1 (v4l) ).
Gcc has some fpu emulation like thing as I can see, and the kernel itself has math emulation.
And as I remember, the "i387" external coprocessor was the hardware fpu unit, not the "386", so if debian ships "386 compatible" binaries it should mean in this context that there are floating point instructions in the code, and it relies on the kernel with fpu emulation?
If the system doesn't have an fpu that is clear. I think the interesting part is for example the T1, 8 cores, 32 threads, but only one fpu. Maybe a threaded emulation in the kernel, or a "workaround" by gcc - as for no fpu arm platforms performs better?
Anyway I will check the sources of the packages ( not the original ones, since debian is not always using the vanilla softwares, and now I focuses on that distribution ).
|
|
|
All times are GMT -5. The time now is 11:40 AM.
|
LinuxQuestions.org is looking for people interested in writing
Editorials, Articles, Reviews, and more. If you'd like to contribute
content, let us know.
|
Latest Threads
LQ News
|
|