> -Original Message-
> From: Miroslav Lichvar
> Sent: Wednesday, June 21, 2023 12:52 AM
> To: Keller, Jacob E
> Cc: linuxptp-users@lists.sourceforge.net
> Subject: Re: [Linuxptp-users] [issue] phc2sys results large jitter with
> multiple '-c'
>
> On Tue,
On Tue, Jun 20, 2023 at 10:07:14PM -0700, Jacob Keller wrote:
> On 6/11/2023 11:53 PM, Miroslav Lichvar wrote:
> > If you need to synchronize multiple PHCs to each other, it's better to
> > use one phc2sys instance to synchronize the system clock to the source
> > PHC and then another phc2sys
On 6/11/2023 11:53 PM, Miroslav Lichvar wrote:
> On Mon, Jun 12, 2023 at 12:24:19PM +0800, egg car wrote:
>> 5) not only the 4 ports on the same nic, any combination of ptp0~ptp9 results
>> the same.
>>
>>
>> Have gone through the phc2sys codes, find nothing reasonable that explains
>> this
Dear Miro,
> Yes, it's related to PCIe delays. The problem is that the kernel
> doesn't provide an ioctl to measure offset between two PHCs, so
> phc2sys has to do it in user space using clock_gettime(), which
> doesn't work very well (large delay, jitter and asymmetry).
Yes it seems like the
On Mon, Jun 12, 2023 at 12:24:19PM +0800, egg car wrote:
> 5) not only the 4 ports on the same nic, any combination of ptp0~ptp9 results
> the same.
>
>
> Have gone through the phc2sys codes, find nothing reasonable that explains
> this issue so far.
>
> I can see when the large jitter happens,
Hi,
Just upgraded to v4.0, and trying the new feature of 'phc2sys' with
multiple '-c'.
It seems not working very well on my test machine, with large offset jitters.
Here's my configuration:
1) ptp0~ptp3 are 4 ports on a 4 port i350, ptp4~ptp9 are separated i210 ports.
2) run ts2phc on
