Kernel mode programming

Zera William Holladay zholla1 at uic.edu
Tue Jan 18 08:10:29 PST 2005



On Tue, 18 Jan 2005, Bruce M Simpson wrote:

> On Tue, Jan 18, 2005 at 11:45:05AM +0100, - Felix - wrote:
> > Doing lot of syscalls interrupts in a soft seems to take quite a long time, and seriously slow performances. As far as you can't reduce the syscall amount, is there any way to run apps in kernel mode, in order to call sysfonctions directly ? Perhaps by re-writing softs in kernel modules ?
>
> For 95% of applications syscall overhead shouldn't have a major impact on
> performance. It's difficult to offer any real advice here because you haven't
> said what the application is, or shown any profiling figures.

Even if the application were run as a kernel module, how much of a
performance benefit could there be when making system calls?  I suspect
that the module would get a higher scheduling priority but realistically
wouldn't the module still have to make system calls in the same manner
that a regular user process does?  I really don't know, so would some kind
soul tell me please?

-Zera Holladay


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