Subject: Re: Kernel compiler flags in the 5-31 sources
To: None <dsndata!sierra!>
From: Mark P. Gooderum <>
List: current-users
Date: 06/03/1994 10:04:53
> I noticed that we are now using -O6 in the compiler flags for kernel builds?
> Did that just change?
> In the past that caused some problems with timers if my memory serves me.
> Has that been resolved?
Noticed this too, but I haven't been having any problems.

> What about adding -m486 for kernels defining that 486CPU?

I've done this manually.  For 2.4.5 this gives about a 5% speed win overall
from what I've measured, however, it causes some noticable code growth,
almost 10%.  My kernel goes from about 575K to 630K with -m486.

Supposedly 2.5.3ish and later give much better speedup with -m586 even with
a 486.  I'll have an OS built with the Cygnus Reno 1.3 (2.5.8) stuff in about
a week and I'll post some comparisons after that.