Re: [Bug 350] New: i386 context switch very slow compared to 2.4 due to wrmsr (performance)

Thomas Molina
2003-03-18T19:03:35Z

> > You can run this (stupid) test-program to try. On my P4 I get
> >
> > empty overhead=320 cycles
> > load overhead=0 cycles
> > I$ load overhead=0 cycles
> > I$ load overhead=0 cycles
> > I$ store overhead=264 cycles

On my Athlon 1.3GHz system I get:
[tmolina@dad tmolina]$ cat /proc/cpuinfo
processor : 0
vendor_id : AuthenticAMD
cpu family : 6
model : 4
model name : AMD Athlon(tm) Processor
stepping : 2
cpu MHz : 1343.030
cache size : 256 KB
fdiv_bug : no
hlt_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 1
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 sep mtrr pge mca cmov
pat pse36 mmx fxsr syscall mmxext 3dnowext 3dnow
bogomips : 2637.82

empty overhead=16 cycles
load overhead=1 cycles
I$ load overhead=1 cycles
I$ load overhead=1 cycles
I$ store overhead=763 cycles