weird interrupt load / exec behaviour

[Matthew Dillon]

:hey,
:
:with my new athlon64 3200+ / NForce4 I am seeing a totally weird=20
:interrupt load when compiling.  Usually the load is at about 80% then=20
:and the box doesn't really compile much faster than my duron 1200=20
:before.
:
:I've narrowed it down to exec.  If I write a program which does nothing=20=
:
:but exec itself in a loop, I will get interrupt loads of > 90%.  I'm=20
:not sure if this is just accounting or real interrupt processing.  At=20
:the same time vmstat -i doesn't show more interrupts than usual.
:
:It's really a pitty that it is so slow for compiling :/
:
:I'll try a GENERIC kernel and a non-mcpu=3Dathlon64 kernel later, but I=20=
:
:doubt this helps.
:
:Any clues?  Where could I start investigating?
:
:cheers
:   simon

    Are you running a completely current world?  I tried the same
    patch:

    /*
     * x.c
     */
    #include <stdio.h>

    main()
    {
	execl("./x", "x", NULL);
    }

    And all I got was system + user time.

					-Matt