DTrace userland project

[Rui Paulo]

On 1 Sep 2010, at 11:20, Marius Nünnerich wrote:

> On Wed, Sep 1, 2010 at 00:21, Rui Paulo <rpaulo at freebsd.org> wrote:
>> Hi,
>> The DTrace userland project is near completion and you can start using parts of it right away (only on FreeBSD HEAD right now).
>> 
>> For more information on how to use DTrace with userland, please read:
>> http://wiki.freebsd.org/DTrace/userland
> 
> Hi,
> 
> I set this up in a VirtualBox with 9-current r212073 amd64, 4-cores,
> amd-v and nested paging enabled.
> I tried
> dtruss /usr/bin/true
> it works but is really slow, it takes ~10s to switch vt.

This is not really using the new userland dtrace code, but the old one. I suspect DTrace has a problem running on your system. Can you try a different VM software or real hardware? I never experienced this problem on VMWare Fusion.

> I tried the pid example as well, if I execute it on ttyv0 I can see lots of
> kernel trap 12 with interrupts disabled
> messages flying by and inbetween the desired _sleep:entry probes. When
> I execute that script on ttyv1 I obviously don't see the kernel trap
> messages and the machine kindof locks up (no output at all). I can do
> a clean ACPI shutdown though.

This looks like I race that I haven't fixed yet. Either way, if the VM is interfering, then it will be hard to find out how to fix this.

Regards,
--
Rui Paulo