linuxptp-users — Open discussion on using the linuxptp software.

Re: [Linuxptp-users] tx_timestamp_timeout and i210

[Keller, J. E <jac...@in...>]

Hi,

Make sure you have disabled EEE support. If EEE is on, then the i210 device can take a very long time to return timestamps if the only traffic running is ptp. (since the link will go to sleep inbetween the frames).

That should be the issue here. If you still see the issue please let me know.

Regards,
Jake

> -----Original Message-----
> From: Axel Holzinger [mailto:aho...@gm...]
> Sent: Monday, June 29, 2015 3:24 PM
> To: lin...@li...
> Subject: [Linuxptp-users] tx_timestamp_timeout and i210
> 
> Hi Richard et al,
> 
> on Ubuntu 14.04 with all updates and latest Intel i210 igb driver I
> regularly get tx_timestamp_timeout error messages with the default
> timeout
> of 1ms. I then changed to 5ms and since then I don't see any more errors.
> 
> Does anybody see similar problems? Might this be a problem of the PC
> (some
> years old HP xw workstation) or might this be a i210 problem?
> 
> Any hint appreciated.
> 
> Regards
> Axel
> 
> 
> 
> ------------------------------------------------------------------------------
> Don't Limit Your Business. Reach for the Cloud.
> GigeNET's Cloud Solutions provide you with the tools and support that
> you need to offload your IT needs and focus on growing your business.
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[Linuxptp-users] tx_timestamp_timeout and i210

[Axel H. <aho...@gm...>]

Hi Richard et al,

on Ubuntu 14.04 with all updates and latest Intel i210 igb driver I
regularly get tx_timestamp_timeout error messages with the default timeout
of 1ms. I then changed to 5ms and since then I don't see any more errors.

Does anybody see similar problems? Might this be a problem of the PC (some
years old HP xw workstation) or might this be a i210 problem?

Any hint appreciated.

Regards
Axel

Re: [Linuxptp-users] Is there a way to query ptp4l or phc2sys status?

[Richard C. <ric...@gm...>]

On Mon, Jun 29, 2015 at 03:12:39PM -0500, Robb wrote:
> Does something like this exist?

Yes, we have the 'pmc' (PTP managment client) for that.  You can query
the local node via UDS or the entire network via normal PTP managment
messages.  The program has both interactive and command line modes.

Some of the queries are:

CURRENT_DATA_SET           for offsetFromMaster and meanPathDelay
PARENT_DATA_SET            find out the GM identity
TIME_PROPERTIES_DATA_SET   find out whether time is globally traceable
PORT_DATA_SET              knowing the portState can be useful, SLAVE and MASTER

You can make a really simple monitoring application using 'watch'
together with 'pmc'.

Cheers,
Richard

Re: [Linuxptp-users] Is there a way to query ptp4l or phc2sys status?

[Insop S. <Ins...@ga...>]

I use a wrapp scrip around pmc.

- use pmc as is, for example


"""
- example pmc outputs

$ pmc -u -b 0  'GET CURRENT_DATA_SET'
sending: GET CURRENT_DATA_SET
	2c553c.fffe.0008b0-0 seq 0 RESPONSE MANAGMENT CURRENT_DATA_SET 
		stepsRemoved     1
		offsetFromMaster 11111
		meanPathDelay    11197.0


$ pmc -u -b 0  'GET TIME_STATUS_NP'
sending: GET TIME_STATUS_NP
	2c553c.fffe.0008b0-0 seq 0 RESPONSE MANAGMENT TIME_STATUS_NP 
		master_offset              111
		ingress_time               92954226412560
		cumulativeScaledRateOffset +0.000000000
		scaledLastGmPhaseChange    0
		gmTimeBaseIndicator        0
		lastGmPhaseChange          0x0000'0000000000000000.0000
		gmPresent                  true
		gmIdentity                 99553c.fffe.0003c0


$ pmc -u -b 0  'GET PORT_DATA_SET'
sending: GET PORT_DATA_SET
	2c553c.fffe.0003c0-1 seq 0 RESPONSE MANAGMENT PORT_DATA_SET 
		portIdentity            99553c.fffe.0003c0-1
		portState               MASTER
		logMinDelayReqInterval  0
		peerMeanPathDelay       0
		logAnnounceInterval     0
		announceReceiptTimeout  3
		logSyncInterval         1
		delayMechanism          1
		logMinPdelayReqInterval 0
		versionNumber           2
"""


- or use this script

output example which can be fed to other program easily

./show-ptp 
SLAVE
SYNC
-106
994a00.fffe.040144
16878.0



--------
- cat show-ptp 

#! /usr/bin/env python

import errno, os
import os.path
import time
import sys
import random

import subprocess
import time
import logging


"""
- example pmc outputs

$ pmc -u -b 0  'GET CURRENT_DATA_SET'
sending: GET CURRENT_DATA_SET
	2c553c.fffe.0008b0-0 seq 0 RESPONSE MANAGMENT CURRENT_DATA_SET 
		stepsRemoved     1
		offsetFromMaster 811103.0
		meanPathDelay    11197.0


$ pmc -u -b 0  'GET TIME_STATUS_NP'
sending: GET TIME_STATUS_NP
	2c553c.fffe.0008b0-0 seq 0 RESPONSE MANAGMENT TIME_STATUS_NP 
		master_offset              811036
		ingress_time               92954226412560
		cumulativeScaledRateOffset +0.000000000
		scaledLastGmPhaseChange    0
		gmTimeBaseIndicator        0
		lastGmPhaseChange          0x0000'0000000000000000.0000
		gmPresent                  true
		gmIdentity                 2c553c.fffe.0003c0


$ pmc -u -b 0  'GET PORT_DATA_SET'
sending: GET PORT_DATA_SET
	2c553c.fffe.0003c0-1 seq 0 RESPONSE MANAGMENT PORT_DATA_SET 
		portIdentity            2c553c.fffe.0003c0-1
		portState               MASTER
		logMinDelayReqInterval  0
		peerMeanPathDelay       0
		logAnnounceInterval     0
		announceReceiptTimeout  3
		logSyncInterval         1
		delayMechanism          1
		logMinPdelayReqInterval 0
		versionNumber           2
"""
# doesn't have to be dict, in case we need a "keyword" based retrieval in the future, so use dict instead of list
ptp_oper_dict = {
		#	[cmd, anchor keywords,...]
		1:	["pmc -u -b 0  'GET PORT_DATA_SET'", 'portState'],
		2:	["pmc -u -b 0  'GET TIME_STATUS_NP'", 'gmPresent', 'master_offset', 'gmIdentity'],
		3:	["pmc -u -b 0  'GET CURRENT_DATA_SET'", 'meanPathDelay']
}

fake_result = [
	[ 'MASTER',
	'MASTER',
	'0',
	'2c553c.fffe.000550',
	'0.0', ],
	[ 'SLAVE',
	'UNCALIBRATED',
	'0',
	'2c553c.fffe.000550',
	'0.0', ]
]

unknown_result = [
	'UNKNOWN',
	'UNKNOWN',
	'0',
	'0',
	'0.0',
]

# run subprocess and returns out, err, errcode
def run_shell2(dir, ctx, args):
	cwd = os.getcwd()
	os.chdir(dir)

	process = subprocess.Popen(args, shell=True,
			stdout=subprocess.PIPE, stderr=subprocess.PIPE)
	out, err = process.communicate()
	errcode = process.returncode
	logging.debug('OK: [%s] %s' % (os.getcwd(), args))

	os.chdir(cwd)

	return out, err, errcode

def get_after_keword(s, keyword):
	b,k,a = s.partition(keyword)
	if k is '':
		return -1, None

	t = a.split('\n')
	t1 = t[0].split()
	return 0, ' '.join(t1)

def check_pmc_exist():
	if os.path.isfile('/usr/bin/pmc'):
		return 0
	return 1


#
# output format: '\n' separated
# > getting>	role/status, gmpresent, offset, gm id, pathdelay
# > returning>	role, status, offset, gm id, pathdelay
# 
def show_ptp_oper(debug):
	result = []

	r = check_pmc_exist()
	if r != 0:
		# return fake data
		print '\n'.join(random.choice(fake_result))
		return -1

	len_dic = len(ptp_oper_dict)
	for key in range(1,len_dic+1):
		cmd = ptp_oper_dict[key][0]
		search_word = ptp_oper_dict[key][1:]
		logging.debug('running %s' % cmd)

		out, err, errcode = run_shell2('.', None, cmd)
		out = out.strip()

		if errcode != 0:
			print '\n'.join(unknown_result)
			return -1

		for item in search_word:
			r, word = get_after_keword(out, item)
			if r == -1:
				print '\n'.join(unknown_result)
				return -1
			result.append(word)

	tmp = result[0]
	tmp1 = result[1]
	if result[1] == "false" and result[0] == "MASTER":
		result[0] = "MASTER"
	else:
		result[0] = "SLAVE"
	
	result[1] = tmp

	if tmp1 == "true":
		if tmp == "SLAVE":
			# state slave and gm present is true
			result[1] = "SYNC"
		elif tmp == "LISTENING":
			# listening and gm present is true
			result[1] = "HOLDOVER"

	print '\n'.join(result)

	return 0

if __name__ == '__main__':

	logging.basicConfig(level=logging.INFO)

	debug = 0
	if len(sys.argv) > 1:
		debug = 1

	r = show_ptp_oper(debug)
	sys.exit(r)





________________________________________
From: Robb <rba...@gm...>
Sent: Monday, June 29, 2015 1:12 PM
To: lin...@li...
Subject: [Linuxptp-users] Is there a way to query ptp4l or phc2sys status?

I have synced the clocks between two machines quite well and was curious
if there is an easy way to query my slave machine from the command line
and determine if the clocks are in sync.

It is obvious to look at the logs and tell that they are currently in
sync, but I was hoping to not have to write a tool to scrape the logs,
also I really would prefer not to log the information anyway.

Does something like this exist?

Thanks.

------------------------------------------------------------------------------
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GigeNET's Cloud Solutions provide you with the tools and support that
you need to offload your IT needs and focus on growing your business.
Configured For All Businesses. Start Your Cloud Today.
https://www.gigenetcloud.com/
_______________________________________________
Linuxptp-users mailing list
Lin...@li...
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[Linuxptp-users] Is there a way to query ptp4l or phc2sys status?

[Robb <rba...@gm...>]

I have synced the clocks between two machines quite well and was curious
if there is an easy way to query my slave machine from the command line
and determine if the clocks are in sync.

It is obvious to look at the logs and tell that they are currently in
sync, but I was hoping to not have to write a tool to scrape the logs,
also I really would prefer not to log the information anyway.

Does something like this exist?

Thanks.

Re: [Linuxptp-users] Interpretation of ptp4l results

[Chandra M. <sma...@al...>]

Hi Richard,

Thank you very much. Yes, I need to look at stats.c block - trying to take advantage of your having gone through it already. I am sorry for that.

Thanking you in anticipation,
Regards,
Chandra

(c) : +60.175508142
(O): +60.4.636.6412

"Knowledge speaks, Wisdom listens"



-----Original Message-----
From: Richard Cochran [mailto:ric...@gm...]
Sent: Monday, June 22, 2015 9:13 PM
To: Chandra Mallela
Cc: Miroslav Lichvar; lin...@li...
Subject: Re: [Linuxptp-users] Interpretation of ptp4l results

On Mon, Jun 22, 2015 at 12:22:01PM +0000, Chandra Mallela wrote:
> Offset correction: the 'rms' (root mean squre - 2 ns in the above
> case) is the mean offset (calculated as squareroot of the mean of the
> offset squares) of all the offsets in the sample observed in the
> interval and 'max' (7ns) is the maximum offset observed within the
> sample.

Yes.

> Frequency correction: Mean frequency deviation observed is 156403 ppb
> with the standard deviation of 7 pbb

Yes.

> (if so, is 7pbb at 3sigma?):

?

> likening it to gaussian/normal distribution

??

> Path delay: the mean value is 28ns and the standard deviation is 0:

Yes.

> likening it to the gaussian/normal distribution

???

Take a look at stats.c to see how the stddev is being calculated.
It is really straightforward.

Thanks,
Richard

________________________________

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Re: [Linuxptp-users] Interpretation of ptp4l results

[Richard C. <ric...@gm...>]

On Mon, Jun 22, 2015 at 12:22:01PM +0000, Chandra Mallela wrote:
> Offset correction: the 'rms' (root mean squre - 2 ns in the above
> case) is the mean offset (calculated as squareroot of the mean of
> the offset squares) of all the offsets in the sample observed in the
> interval and 'max' (7ns) is the maximum offset observed within the
> sample.

Yes.

> Frequency correction: Mean frequency deviation observed is 156403
> ppb with the standard deviation of 7 pbb

Yes.

> (if so, is 7pbb at 3sigma?):

?

> likening it to gaussian/normal distribution

??

> Path delay: the mean value is 28ns and the standard deviation is 0:

Yes.

> likening it to the gaussian/normal distribution

???

Take a look at stats.c to see how the stddev is being calculated.
It is really straightforward.

Thanks,
Richard

Re: [Linuxptp-users] Interpretation of ptp4l results

[Chandra M. <sma...@al...>]

Hi Richard,

Sorry for belaboring on this.

Can I then confirm the following mathematical definitions of the ptp4l repor, based on our mail threadt? This helps all of us (mostly rookies like me) to be on clear mathematical understanding of what is reported.

When ptp4l reports:  ptp4l[833.369]: rms    2 max    7 freq -156403 +/-   7 delay    28 +/-   0


Offset correction: the 'rms' (root mean squre - 2 ns in the above case) is the mean offset (calculated as squareroot of the mean of the offset squares) of all the offsets in the sample observed in the interval and 'max' (7ns) is the maximum offset observed within the sample.
Frequency correction: Mean frequency deviation observed is 156403 ppb with the standard deviation of 7 pbb (if so, is 7pbb at 3sigma?): likening it to gaussian/normal distribution
Path delay: the mean value is 28ns and the standard deviation is 0: likening it to the gaussian/normal distribution

Thanking you in anticipation,
Regards,
Chandra

(c) : +60.175508142
(O): +60.4.636.6412

"Knowledge speaks, Wisdom listens"



-----Original Message-----
From: Richard Cochran [mailto:ric...@gm...]
Sent: Monday, June 22, 2015 2:31 PM
To: Chandra Mallela
Cc: Miroslav Lichvar; lin...@li...
Subject: Re: [Linuxptp-users] Interpretation of ptp4l results

On Sun, Jun 21, 2015 at 11:09:08PM +0000, Chandra Mallela wrote:

> However, you mention that 'max' for the offset is simply the maximum
> offset observed in the sample. In that case, do frequency correction
> and offset correction values differ in their definitions (with 7ns in
> the offset defining the max offset in the sample whereas 7 pbb in the
> frequency showing the maximum deviation from the mean)?

These are two different parameters, and they are indeed defined differently.  The offset is the observed offset based on the result of the PTP.  The frequency is the output from the servo, and it is only indirectly related to the observed offset.  For example, using a weak proportional weight, you will have see a smaller range of frequencies.
Or if you prohibit resetting the clock, a large offset will cause a constant frequency value (steering using the maximum possible value).

HTH,
Richard

________________________________

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Re: [Linuxptp-users] Interpretation of ptp4l results

[Richard C. <ric...@gm...>]

On Sun, Jun 21, 2015 at 11:09:08PM +0000, Chandra Mallela wrote:

> However, you mention that 'max' for the offset is simply the maximum
> offset observed in the sample. In that case, do frequency correction
> and offset correction values differ in their definitions (with 7ns
> in the offset defining the max offset in the sample whereas 7 pbb in
> the frequency showing the maximum deviation from the mean)?

These are two different parameters, and they are indeed defined
differently.  The offset is the observed offset based on the result of
the PTP.  The frequency is the output from the servo, and it is only
indirectly related to the observed offset.  For example, using a weak
proportional weight, you will have see a smaller range of frequencies.
Or if you prohibit resetting the clock, a large offset will cause a
constant frequency value (steering using the maximum possible value).

HTH,
Richard

Re: [Linuxptp-users] sanity_freq_limit

[Richard C. <ric...@gm...>]

On Mon, Jun 22, 2015 at 03:35:19AM +0000, Daniel Le wrote:
> Does ptp4l step only once (assuming the default first_step_threshold of 20 microseconds is met) no matter how master offsets vary afterward?

No, you can step a second and subsequent times by setting
'step_threshold' to a non-zero value.

HTH,
Richard

Re: [Linuxptp-users] sanity_freq_limit

[Daniel Le <dan...@ex...>]

Does ptp4l step only once (assuming the default first_step_threshold of 20 microseconds is met) no matter how master offsets vary afterward?

Daniel

-----Original Message-----
From: Daniel Le 
Sent: Friday, June 19, 2015 4:10 PM
To: 'Richard Cochran'
Cc: Lin...@li...
Subject: Re: [Linuxptp-users] sanity_freq_limit

"...or that the change in time is not reflected in the subsequent time stamps". This is a good pointer for debugging. The system clock may have been stepped, but the FPGA hardware clock is not stepped and continues to provide the timestamps from its un-stepped clock.

Much appreciate it.
Daniel

-----Original Message-----
From: Richard Cochran [mailto:ric...@gm...]
Sent: Friday, June 19, 2015 3:59 PM
To: Daniel Le
Cc: Lin...@li...
Subject: Re: [Linuxptp-users] sanity_freq_limit

On Fri, Jun 19, 2015 at 07:43:01PM +0000, Daniel Le wrote:
> 
> PHC is not used in my system. I have a proprietary NIC FPGA-based MAC 
> driver which has its own hardware clock, and in this scheme, 
> synchronizes to the Linux system clock that in turn is synchronized to 
> PTP Grandmaster via software timestamping mechanism. The timestamps of 
> PTP packets are provided by the FPGA MAC driver may cause problem. It 
> seems that the system clock fails to be stepped.

Okay, so you have a special custom setup.  I cannot really guess what is wrong, but it does appear that whatever clock you are using is failing to jump, or that the change in time is not reflected in the subsequent time stamps.

Thanks,
Richard

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Re: [Linuxptp-users] Interpretation of ptp4l results

[Chandra M. <sma...@al...>]

Hi Miroslav et al,

Perhaps I am not clear about my question - just would like to understand the mathematical interpretation of the following for the offset and frequency corrections. For example, in the following output,

Frequency correction: Average frequency deviation observed is 156403 ppb with the maximum deviation of 7 pbb.

Offset correction: the 'rms' (root mean squre) is the mean offset of all the offsets in the sample observed in the interval and 'max' is the maximum deviation observed from the rms value.


However, you mention that 'max' for the offset is simply the maximum offset observed in the sample. In that case, do frequency correction and offset correction values differ in their definitions (with 7ns in the offset defining the max offset in the sample whereas 7 pbb in the frequency showing the maximum deviation from the mean)?


ptp4l[833.369]: rms    2 max    7 freq -156403 +/-   7 delay    28 +/-   0

Thanking you in anticipation,
Regards,
Chandra

(c) : +60.175508142
(O): +60.4.636.6412

"Knowledge speaks, Wisdom listens"


-----Original Message-----
From: Chandra Mallela
Sent: Saturday, June 20, 2015 12:41 AM
To: 'Miroslav Lichvar'
Cc: lin...@li...
Subject: RE: [Linuxptp-users] Interpretation of ptp4l results



Hi Miroslav,

My question is about mathematical interpretation of the output from the ptp4l stack. If I see the output like the one below, is it fair to assume that the 'rms' (root mean squre) is the mean offset of all the sample offsets observed in the interval and 'max' is the maximum deviation observed from the rms value? I am likening it to kinda gaussian/normal distribution but without sign interpretation. Otherwise, I am fully in line with what you have mentioned below.

ptp4l[833.369]: rms    2 max    7 freq -156403 +/-   7 delay    28 +/-   0

Thanking you in anticipation,
Regards,
Chandra

(c) : +60.175508142
(O): +60.4.636.6412

"Knowledge speaks, Wisdom listens"



-----Original Message-----
From: Miroslav Lichvar [mailto:mli...@re...]
Sent: Friday, June 19, 2015 4:23 PM
To: Chandra Mallela
Cc: lin...@li...
Subject: Re: [Linuxptp-users] Interpretation of ptp4l results

On Fri, Jun 19, 2015 at 07:53:52AM +0000, Chandra Mallela wrote:
>
>
> Hi Friends,
>
> I would like to double-check whether my following interpretation is correct. Please elucidate me.
>
> For the following ptp4l output, the ptp4l reports rms value and the max deviation from the mean offset. Thus, if I have to report the worstcase accuracy, I take the (rms+max). For example, , looking at the first line, I see that the maximum offset uncertainty/inaccuracy  observed is 2 +7 = 9ns. The maximum frequency uncertainty is (156403 + 7) pbb.

The max value is just the maximum measured offset in that interval. It doesn't mean it's also the worst accuracy of the clock. There could be an asymmetry in the network delay and ptp4l wouldn't know the clock is actually behind or ahead of the time source. To evaluate the accuracy you would to measure the error independendly from PTP, for example by comparing PPS signal generated by the synchronized clock with the reference on a scope.

--
Miroslav Lichvar

________________________________

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This message may contain information that is confidential or otherwise protected from disclosure. If you are not the intended recipient, you are hereby notified that any use, disclosure, dissemination, distribution, or copying of this message, or any attachments, is strictly prohibited. If you have received this message in error, please advise the sender by reply e-mail, and delete the message and any attachments. Thank you.

Re: [Linuxptp-users] How to configure linuxptp

[Caleb Yu <cal...@gm...>]

Thank you Richard. I will try it out.
Caleb
On Jun 20, 2015 10:56 PM, "Richard Cochran" <ric...@gm...>
wrote:

> On Sat, Jun 20, 2015 at 06:59:07PM +0800, Caleb Yu wrote:
> > To Richard:
> > Thank you for replying so fast. Which file can I go and see what each
> > configurations options like -m, -q configure? -m should master mode
> right?
>
> No, '-m' is to print the program's output to the terminal.
> You can get a summary of the command line options like this:
>
>    ptp4l -h
>
> To read the complete documentation, enter this command:
>
>    man ptp4l
>
> If you didn't run "make install", then you can simply read the man
> page in place:
>
>    man -l ptp4l.8
>
> The other programs, phc2sys and pmc, also have man pages.
>
> Cheers,
> Richard
>

Re: [Linuxptp-users] How to configure linuxptp

[Richard C. <ric...@gm...>]

On Sat, Jun 20, 2015 at 06:59:07PM +0800, Caleb Yu wrote:
> To Richard:
> Thank you for replying so fast. Which file can I go and see what each
> configurations options like -m, -q configure? -m should master mode right?

No, '-m' is to print the program's output to the terminal.
You can get a summary of the command line options like this:

   ptp4l -h

To read the complete documentation, enter this command:

   man ptp4l

If you didn't run "make install", then you can simply read the man
page in place:

   man -l ptp4l.8

The other programs, phc2sys and pmc, also have man pages.

Cheers,
Richard

Re: [Linuxptp-users] How to configure linuxptp

[Caleb Yu <cal...@gm...>]

To Richard:
Thank you for replying so fast. Which file can I go and see what each
configurations options like -m, -q configure? -m should master mode right?
This will help me to able to have more advanced configuration if needed.
Thank you again. I am looking forwarding to using the program.
Sincerely,
Caleb

2015-06-20 18:34 GMT+08:00 Richard Cochran <ric...@gm...>:

> On Sat, Jun 20, 2015 at 02:55:35PM +0800, Caleb Yu wrote:
> > To whom it may interest,
> > I am new to linuxptp. I have not able to check on Linux-users archive yet
> > since I just recently added due to read access required error.
>
> Archives on Gmane:
>
>   http://news.gmane.org/gmane.comp.linux.ptp.devel
>   http://news.gmane.org/gmane.comp.linux.ptp.user
>
> > I have
> > installed linuxptp according to the website but I don't know the commands
> > to configure or start it. I searched around a little bit but not able to
> > find what I need. It will help a lot if I get to know how to use this
> > program. Thank you.
>
> The easiest way to start is like this:
>
>   ptp4l -m -q -i eth0
>
> If your MAC only has SW time stamping, then add '-S' to the command line.
>
> Everything else depends on your special requirements, but if you don't
> have any, then you also don't need any other options.
>
> HTH,
> Richard
>

Re: [Linuxptp-users] How to configure linuxptp

[Richard C. <ric...@gm...>]

On Sat, Jun 20, 2015 at 02:55:35PM +0800, Caleb Yu wrote:
> To whom it may interest,
> I am new to linuxptp. I have not able to check on Linux-users archive yet
> since I just recently added due to read access required error.

Archives on Gmane:

  http://news.gmane.org/gmane.comp.linux.ptp.devel
  http://news.gmane.org/gmane.comp.linux.ptp.user

> I have
> installed linuxptp according to the website but I don't know the commands
> to configure or start it. I searched around a little bit but not able to
> find what I need. It will help a lot if I get to know how to use this
> program. Thank you.

The easiest way to start is like this:

  ptp4l -m -q -i eth0

If your MAC only has SW time stamping, then add '-S' to the command line.

Everything else depends on your special requirements, but if you don't
have any, then you also don't need any other options.

HTH,
Richard

[Linuxptp-users] How to configure linuxptp

[Caleb Yu <cal...@gm...>]

To whom it may interest,
I am new to linuxptp. I have not able to check on Linux-users archive yet
since I just recently added due to read access required error. I have
installed linuxptp according to the website but I don't know the commands
to configure or start it. I searched around a little bit but not able to
find what I need. It will help a lot if I get to know how to use this
program. Thank you.
Caleb

Re: [Linuxptp-users] sanity_freq_limit

[Miroslav L. <mli...@re...>]

On Fri, Jun 19, 2015 at 09:08:56PM +0200, Richard Cochran wrote:
> On Fri, Jun 19, 2015 at 06:12:53PM +0000, Daniel Le wrote:
> > Thanks Miroslav and Jake.
> > 
> > I'm running linuxptp-1.4 and Linux kernel 2.6.35.7 with customization. My older linuxptp version has pi_f_offset_const instead of first_step_threshold, which I didn't alter.
> > 
> > I added debugging code to confirm that the step takes place, however unclear how things are afterward.
> 
> The issue is probably a bug in your backport of the PHC code, or in
> the backported MAC driver.

He has SW timestamping. Maybe the kernel is missing ADJ_SETOFFSET
support? It would explaing why the step doesn't work. It seems it
appeared in kernel 2.6.39.

-- 
Miroslav Lichvar

Re: [Linuxptp-users] sanity_freq_limit

[Daniel Le <dan...@ex...>]

"...or that the change in time is not reflected in the subsequent time stamps". This is a good pointer for debugging. The system clock may have been stepped, but the FPGA hardware clock is not stepped and continues to provide the timestamps from its un-stepped clock.

Much appreciate it.
Daniel

-----Original Message-----
From: Richard Cochran [mailto:ric...@gm...] 
Sent: Friday, June 19, 2015 3:59 PM
To: Daniel Le
Cc: Lin...@li...
Subject: Re: [Linuxptp-users] sanity_freq_limit

On Fri, Jun 19, 2015 at 07:43:01PM +0000, Daniel Le wrote:
> 
> PHC is not used in my system. I have a proprietary NIC FPGA-based MAC 
> driver which has its own hardware clock, and in this scheme, 
> synchronizes to the Linux system clock that in turn is synchronized to 
> PTP Grandmaster via software timestamping mechanism. The timestamps of 
> PTP packets are provided by the FPGA MAC driver may cause problem. It 
> seems that the system clock fails to be stepped.

Okay, so you have a special custom setup.  I cannot really guess what is wrong, but it does appear that whatever clock you are using is failing to jump, or that the change in time is not reflected in the subsequent time stamps.

Thanks,
Richard

Re: [Linuxptp-users] sanity_freq_limit

[Richard C. <ric...@gm...>]

On Fri, Jun 19, 2015 at 07:43:01PM +0000, Daniel Le wrote:
> 
> PHC is not used in my system. I have a proprietary NIC FPGA-based
> MAC driver which has its own hardware clock, and in this scheme,
> synchronizes to the Linux system clock that in turn is synchronized
> to PTP Grandmaster via software timestamping mechanism. The
> timestamps of PTP packets are provided by the FPGA MAC driver may
> cause problem. It seems that the system clock fails to be stepped.

Okay, so you have a special custom setup.  I cannot really guess what
is wrong, but it does appear that whatever clock you are using is
failing to jump, or that the change in time is not reflected in the
subsequent time stamps.

Thanks,
Richard

Re: [Linuxptp-users] sanity_freq_limit

[Daniel Le <dan...@ex...>]

My understanding is that clkid 0 is CLOCK_REALTIME, which is the system time, based on the definitions in Linux time.h. In the following, the master offset  remains high (497918992) after the system clock is stepped and after the PTP enters Slave mode. Does it mean that the system clock is not actually not stepped?

ptp4l[841551.567]: master offset  497923672 s1 freq  -11601 path delay      1182
ptp4l[841551.567]: Step system clock...
ptp4l[841551.567]: clockadj_set_freq: clkid=0 freq= +11601
ptp4l[841551.567]: clockadj_step: clkid=0 step= 497923672
ptp4l[841552.567]: master offset  497921336 s2 freq +50278454 path delay      1182
ptp4l[841552.567]: clockadj_set_freq: clkid=0 freq= +21546
ptp4l[841552.567]: port 1: UNCALIBRATED to SLAVE on MASTER_CLOCK_SELECTED
ptp4l[841553.517]: master offset  497918992 s2 freq +50776139 path delay      1222
ptp4l[841553.517]: clockadj_set_freq: clkid=0 freq= +23861
ptp4l[841554.466]: master offset  418089084 s2 freq +43211237 path delay  24354298
ptp4l[841554.466]: clockadj_set_freq: clkid=0 freq= -11237

PHC is not used in my system. I have a proprietary NIC FPGA-based MAC driver which has its own hardware clock, and in this scheme, synchronizes to the Linux system clock that in turn is synchronized to PTP Grandmaster via software timestamping mechanism. The timestamps of PTP packets are provided by the FPGA MAC driver may cause problem. It seems that the system clock fails to be stepped.

Thanks!
Daniel

-----Original Message-----
From: Richard Cochran [mailto:ric...@gm...] 
Sent: Friday, June 19, 2015 3:09 PM
To: Daniel Le
Cc: 'Miroslav Lichvar'; Lin...@li...
Subject: Re: [Linuxptp-users] sanity_freq_limit

On Fri, Jun 19, 2015 at 06:12:53PM +0000, Daniel Le wrote:
> Thanks Miroslav and Jake.
> 
> I'm running linuxptp-1.4 and Linux kernel 2.6.35.7 with customization. My older linuxptp version has pi_f_offset_const instead of first_step_threshold, which I didn't alter.
> 
> I added debugging code to confirm that the step takes place, however unclear how things are afterward.

The issue is probably a bug in your backport of the PHC code, or in the backported MAC driver.

Thanks,
Richard

Re: [Linuxptp-users] sanity_freq_limit

[Richard C. <ric...@gm...>]

On Fri, Jun 19, 2015 at 06:12:53PM +0000, Daniel Le wrote:
> Thanks Miroslav and Jake.
> 
> I'm running linuxptp-1.4 and Linux kernel 2.6.35.7 with customization. My older linuxptp version has pi_f_offset_const instead of first_step_threshold, which I didn't alter.
> 
> I added debugging code to confirm that the step takes place, however unclear how things are afterward.

The issue is probably a bug in your backport of the PHC code, or in
the backported MAC driver.

Thanks,
Richard

Re: [Linuxptp-users] sanity_freq_limit

[Daniel Le <dan...@ex...>]

Thanks Miroslav and Jake.

I'm running linuxptp-1.4 and Linux kernel 2.6.35.7 with customization. My older linuxptp version has pi_f_offset_const instead of first_step_threshold, which I didn't alter.

I added debugging code to confirm that the step takes place, however unclear how things are afterward.

(1) On one slave clock device, where its system time is off by 1 hour and 35 minutes behind.

Jun 19 14:31:24 (none) user.warn ptp4l: [16.960] port 1: get_ts_info not supported
Jun 19 14:31:24 (none) user.notice ptp4l: [16.961] port 1: INITIALIZING to LISTENING on INITIALIZE
Jun 19 14:31:24 (none) user.notice ptp4l: [16.961] port 0: INITIALIZING to LISTENING on INITIALIZE
Jun 19 14:31:26 (none) user.notice ptp4l: [18.886] port 1: new foreign master 00b0ae.fffe.02d104-1
Jun 19 14:31:30 (none) user.notice ptp4l: [22.886] selected best master clock 00b0ae.fffe.02d104
Jun 19 14:31:30 (none) user.notice ptp4l: [22.886] port 1: LISTENING to UNCALIBRATED on RS_SLAVE
Jun 19 14:31:30 (none) user.notice ptp4l: [23.118] port 1: minimum delay request interval 2^-7
Jun 19 14:31:33 (none) user.info ptp4l: [25.823] master offset -5479246314194 s0 freq      +0 path delay      3492
Jun 19 14:31:34 (none) user.info ptp4l: [26.823] master offset -5479246315624 s0 freq      +0 path delay      3550
Jun 19 14:31:35 (none) user.info ptp4l: [27.823] master offset -5479246316774 s0 freq      +0 path delay      3512
Jun 19 14:31:36 (none) user.info ptp4l: [28.822] master offset -5479246318180 s0 freq      +0 path delay      3542
Jun 19 14:31:37 (none) user.info ptp4l: [29.822] master offset -5479246319340 s0 freq      +0 path delay      3486
Jun 19 14:31:38 (none) user.info ptp4l: [30.822] master offset -5479247196552 s0 freq      +0 path delay    295486
Jun 19 14:31:39 (none) user.info ptp4l: [31.822] master offset -5479246905902 s0 freq      +0 path delay      3520
Jun 19 14:31:40 (none) user.info ptp4l: [32.822] master offset -5479246907136 s0 freq      +0 path delay      3506
Jun 19 14:31:41 (none) user.info ptp4l: [33.822] master offset -5479246908448 s0 freq      +0 path delay      3538
Jun 19 14:31:42 (none) user.info ptp4l: [34.822] master offset -5479246909704 s0 freq      +0 path delay      3514
Jun 19 14:31:43 (none) user.info ptp4l: [35.822] master offset -5479247782844 s0 freq      +0 path delay    294126
Jun 19 14:31:44 (none) user.info ptp4l: [36.822] master offset -5479247493484 s0 freq      +0 path delay      3518
Jun 19 14:31:45 (none) user.info ptp4l: [37.821] master offset -5479247494752 s0 freq      +0 path delay      3538
Jun 19 14:31:46 (none) user.info ptp4l: [38.821] master offset -5479247496104 s0 freq      +0 path delay      3546
Jun 19 14:31:47 (none) user.info ptp4l: [39.821] master offset -5479247497316 s0 freq      +0 path delay      3514
Jun 19 14:31:48 (none) user.info ptp4l: [40.821] master offset -5479247498658 s0 freq      +0 path delay      3540
Jun 19 14:31:49 (none) user.info ptp4l: [41.821] master offset -5479248375064 s1 freq -128819 path delay    295242
Jun 19 14:31:49 (none) user.info ptp4l: [41.821] Step system clock...
Jun 19 14:31:49 (none) user.info ptp4l: [41.821] clockadj_set_freq: clkid=0 freq= +28819
Jun 19 14:31:49 (none) user.info ptp4l: [41.821] clockadj_step: clkid=0 step=5479248375064
Jun 19 14:31:50 (none) user.info ptp4l: [42.821] master offset -5479248376376 s2 freq -100000000 path delay    295242
Jun 19 14:31:50 (none) user.info ptp4l: [42.821] clockadj_set_freq: clkid=0 freq=     +0
Jun 19 14:31:50 (none) user.notice ptp4l: [42.821] port 1: UNCALIBRATED to SLAVE on MASTER_CLOCK_SELECTED
Jun 19 14:31:51 (none) user.info ptp4l: [43.921] master offset -5479248085876 s2 freq -100000000 path delay      3494
Jun 19 14:31:51 (none) user.info ptp4l: [43.921] clockadj_set_freq: clkid=0 freq=     +0
Jun 19 14:31:52 (none) user.info ptp4l: [45.021] master offset -5479248087212 s2 freq -100000000 path delay      3518
Jun 19 14:31:52 (none) user.info ptp4l: [45.021] clockadj_set_freq: clkid=0 freq=     +0
Jun 19 14:31:53 (none) user.info ptp4l: [46.121] master offset -5479248088444 s2 freq -100000000 path delay      3502
Jun 19 14:31:53 (none) user.info ptp4l: [46.121] clockadj_set_freq: clkid=0 freq=     +0
Jun 19 14:31:55 (none) user.info ptp4l: [47.221] master offset -5479200033936 s2 freq -100000000 path delay -14414590
Jun 19 14:31:55 (none) user.info ptp4l: [47.221] clockadj_set_freq: clkid=0 freq=     +0
Jun 19 14:31:56 (none) user.info ptp4l: [48.320] master offset -5478966697088 s2 freq -100000000 path delay -81086222
Jun 19 14:31:56 (none) user.info ptp4l: [48.321] clockadj_set_freq: clkid=0 freq=     +0
Jun 19 14:31:57 (none) user.info ptp4l: [49.420] master offset -5478802913984 s2 freq -100000000 path delay -78204170
Jun 19 14:31:57 (none) user.info ptp4l: [49.420] clockadj_set_freq: clkid=0 freq=     +0
Jun 19 14:31:58 (none) user.info ptp4l: [50.520] master offset -5478862522102 s2 freq -100000000 path delay  -6196760
Jun 19 14:31:58 (none) user.info ptp4l: [50.520] clockadj_set_freq: clkid=0 freq=     +0
Jun 19 14:31:59 (none) user.info ptp4l: [51.620] master offset -5478868723712 s2 freq -100000000 path delay      3538
Jun 19 14:31:59 (none) user.info ptp4l: [51.620] clockadj_set_freq: clkid=0 freq=     +0
Jun 19 14:32:00 (none) user.info ptp4l: [52.720] master offset -5478868724940 s2 freq -100000000 path delay      3518
Jun 19 14:32:00 (none) user.info ptp4l: [52.720] clockadj_set_freq: clkid=0 freq=     +0
Jun 19 14:32:01 (none) user.info ptp4l: [53.820] master offset -5478710523928 s2 freq -100000000 path delay -50266518
Jun 19 14:32:01 (none) user.info ptp4l: [53.820] clockadj_set_freq: clkid=0 freq=     +0
Jun 19 14:32:02 (none) user.info ptp4l: [54.920] master offset -5478513781464 s2 freq -100000000 path delay -80343798
Jun 19 14:32:02 (none) user.info ptp4l: [54.920] clockadj_set_freq: clkid=0 freq=     +0

(2) On another slave clock device, where its system time is almost same as the correct time.

sbin #ptp4l -m -q -i eth3 -s -S
ptp4l[841529.107]: clockadj_set_freq: clkid=0 freq= -25768
ptp4l[841529.107]: port 1: get_ts_info not supported
ptp4l[841529.108]: port 1: INITIALIZING to LISTENING on INITIALIZE
ptp4l[841529.108]: port 0: INITIALIZING to LISTENING on INITIALIZE
ptp4l[841529.628]: port 1: new foreign master 00b0ae.fffe.02d103-1
ptp4l[841533.629]: selected best master clock 00b0ae.fffe.02d103
ptp4l[841533.629]: port 1: LISTENING to UNCALIBRATED on RS_SLAVE
ptp4l[841533.709]: port 1: minimum delay request interval 2^-7
ptp4l[841535.566]: master offset  496921588 s0 freq  -74232 path delay      1186
ptp4l[841536.566]: master offset  496919220 s0 freq  -74232 path delay      1214
ptp4l[841537.566]: master offset  497436366 s0 freq  -74232 path delay   -171964
ptp4l[841538.567]: master offset  497260880 s0 freq  -74232 path delay      1186
ptp4l[841539.567]: master offset  497258554 s0 freq  -74232 path delay      1212
ptp4l[841540.567]: master offset  497256258 s0 freq  -74232 path delay      1204
ptp4l[841541.567]: master offset  497253920 s0 freq  -74232 path delay      1202
ptp4l[841542.567]: master offset  497251618 s0 freq  -74232 path delay      1200
ptp4l[841543.567]: master offset  497768934 s0 freq  -74232 path delay   -172016
ptp4l[841544.567]: master offset  497593414 s0 freq  -74232 path delay      1196
ptp4l[841545.567]: master offset  497591074 s0 freq  -74232 path delay      1204
ptp4l[841546.567]: master offset  497588774 s0 freq  -74232 path delay      1200
ptp4l[841547.567]: master offset  497586420 s0 freq  -74232 path delay      1218
ptp4l[841548.567]: master offset  498103830 s0 freq  -74232 path delay   -172036
ptp4l[841549.567]: master offset  497928290 s0 freq  -74232 path delay      1204
ptp4l[841550.567]: master offset  497925954 s0 freq  -74232 path delay      1204
ptp4l[841551.567]: master offset  497923672 s1 freq  -11601 path delay      1182
ptp4l[841551.567]: Step system clock...
ptp4l[841551.567]: clockadj_set_freq: clkid=0 freq= +11601
ptp4l[841551.567]: clockadj_step: clkid=0 step= 497923672
ptp4l[841552.567]: master offset  497921336 s2 freq +50278454 path delay      1182
ptp4l[841552.567]: clockadj_set_freq: clkid=0 freq= +21546
ptp4l[841552.567]: port 1: UNCALIBRATED to SLAVE on MASTER_CLOCK_SELECTED
ptp4l[841553.517]: master offset  497918992 s2 freq +50776139 path delay      1222
ptp4l[841553.517]: clockadj_set_freq: clkid=0 freq= +23861
ptp4l[841554.466]: master offset  418089084 s2 freq +43211237 path delay  24354298
ptp4l[841554.466]: clockadj_set_freq: clkid=0 freq= -11237
ptp4l[841555.423]: master offset  403879084 s2 freq +42194116 path delay  12854794
ptp4l[841555.423]: clockadj_set_freq: clkid=0 freq=  +5884
ptp4l[841556.381]: master offset  416730386 s2 freq +43895976 path delay      1188
ptp4l[841556.381]: clockadj_set_freq: clkid=0 freq=  +4024
ptp4l[841557.337]: master offset  416728028 s2 freq +44312469 path delay      1206
ptp4l[841557.337]: clockadj_set_freq: clkid=0 freq= -12469
ptp4l[841558.293]: master offset  416725754 s2 freq +44728967 path delay      1180
ptp4l[841558.293]: clockadj_set_freq: clkid=0 freq= -28967
ptp4l[841559.248]: master offset  416723444 s2 freq +45145459 path delay      1186
ptp4l[841559.248]: clockadj_set_freq: clkid=0 freq= -45459
ptp4l[841560.203]: master offset  416721094 s2 freq +45561946 path delay      1200
ptp4l[841560.203]: clockadj_set_freq: clkid=0 freq= +38054
ptp4l[841561.157]: master offset  389860090 s2 freq +43265705 path delay   7781368
ptp4l[841561.157]: clockadj_set_freq: clkid=0 freq= +34295
ptp4l[841562.114]: master offset  186064456 s2 freq +23072206 path delay  68717870
ptp4l[841562.114]: clockadj_set_freq: clkid=0 freq= +27794
ptp4l[841563.091]: master offset   43535162 s2 freq +8862812 path delay  68388060
ptp4l[841563.091]: clockadj_set_freq: clkid=0 freq= +37188

I also added code to verify if the servo reset occurs when the calculated offset is higher than default sanity_freq_limit.

Jun 18 20:08:59 (none) user.warn ptp4l: [521.858] clockcheck: clock jumped backward or running slower than expected!
Jun 18 20:08:59 (none) user.info ptp4l: [521.858] MAX-foffset=-206031909 flimit=200000000
Jun 18 20:08:59 (none) user.info ptp4l: [521.858] pi_reset .....................
Jun 18 20:08:59 (none) user.warn ptp4l: [521.966] clockcheck: clock jumped forward or running faster than expected!
Jun 18 20:08:59 (none) user.info ptp4l: [521.966] MIN-foffset=+267792097 flimit=200000000
Jun 18 20:08:59 (none) user.info ptp4l: [521.966] pi_reset .....................
Jun 18 20:08:59 (none) user.info ptp4l: [522.070] master offset    1015988 s0 freq +108331 path delay      3518
Jun 18 20:09:00 (none) user.info ptp4l: [523.070] master offset    1014652 s0 freq +108331 path delay      3542
Jun 18 20:09:01 (none) user.info ptp4l: [524.070] master offset    1013376 s0 freq +108331 path delay      3538
Jun 18 20:09:02 (none) user.info ptp4l: [525.070] master offset     924804 s0 freq +108331 path delay     32622
Jun 18 20:09:03 (none) user.info ptp4l: [526.070] master offset     952644 s0 freq +108331 path delay      3506
Jun 18 20:09:04 (none) user.info ptp4l: [527.070] master offset     951354 s0 freq +108331 path delay      3512

-----Original Message-----
From: Miroslav Lichvar [mailto:mli...@re...] 
Sent: Friday, June 19, 2015 4:04 AM
To: Daniel Le
Cc: Lin...@li...
Subject: Re: [Linuxptp-users] sanity_freq_limit

On Fri, Jun 19, 2015 at 04:15:20AM +0000, Daniel Le wrote:
> And the log messages at start in "good case". I didn't save the log where my system time was initially off a few minutes, though I remember the master offsets were above 200000000. I'll need to reproduce such condition in order to capture the exact log messages.

Your config looks good to me. The default value of first_step_threshold is 20 microseconds, so in your test with ~1.5 millisecond initial offset it should have stepped.

> ptp4l[792717.068]: master offset   -1567668 s0 freq  -13556 path delay      1194
> ptp4l[792718.068]: master offset   -1569978 s0 freq  -13556 path delay      1200
> ptp4l[792719.068]: master offset   -1554292 s1 freq  -13510 path delay     -4826
> ptp4l[792720.068]: master offset   -1556592 s2 freq -170726 path delay     -4826

But as we can see, it didn't step for some reason. Here is a test I did using the same config file and it does step for me.

ptp4l[8898442.271]: master offset   -1093869 s0 freq   -1946 path delay     54642
ptp4l[8898443.271]: master offset   -1094931 s0 freq   -1946 path delay     54642
ptp4l[8898444.271]: master offset   -1102224 s1 freq   -6078 path delay     55329
ptp4l[8898445.271]: master offset       9378 s2 freq   -5131 path delay     55329

What linuxptp and kernel versions are you using?

--
Miroslav Lichvar

Re: [Linuxptp-users] Interpretation of ptp4l results

[Chandra M. <sma...@al...>]

Hi Miroslav,

My question is about mathematical interpretation of the output from the ptp4l stack. If I see the output like the one below, is it fair to assume that the 'rms' (root mean squre) is the mean offset of all the sample offsets observed in the interval and 'max' is the maximum deviation observed from the rms value? I am likening it to kinda gaussian/normal distribution but without sign interpretation. Otherwise, I am fully in line with what you have mentioned below.

ptp4l[833.369]: rms    2 max    7 freq -156403 +/-   7 delay    28 +/-   0

Thanking you in anticipation,
Regards,
Chandra

(c) : +60.175508142
(O): +60.4.636.6412

"Knowledge speaks, Wisdom listens"



-----Original Message-----
From: Miroslav Lichvar [mailto:mli...@re...]
Sent: Friday, June 19, 2015 4:23 PM
To: Chandra Mallela
Cc: lin...@li...
Subject: Re: [Linuxptp-users] Interpretation of ptp4l results

On Fri, Jun 19, 2015 at 07:53:52AM +0000, Chandra Mallela wrote:
>
>
> Hi Friends,
>
> I would like to double-check whether my following interpretation is correct. Please elucidate me.
>
> For the following ptp4l output, the ptp4l reports rms value and the max deviation from the mean offset. Thus, if I have to report the worstcase accuracy, I take the (rms+max). For example, , looking at the first line, I see that the maximum offset uncertainty/inaccuracy  observed is 2 +7 = 9ns. The maximum frequency uncertainty is (156403 + 7) pbb.

The max value is just the maximum measured offset in that interval. It doesn't mean it's also the worst accuracy of the clock. There could be an asymmetry in the network delay and ptp4l wouldn't know the clock is actually behind or ahead of the time source. To evaluate the accuracy you would to measure the error independendly from PTP, for example by comparing PPS signal generated by the synchronized clock with the reference on a scope.

--
Miroslav Lichvar

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Re: [Linuxptp-users] Interpretation of ptp4l results

[Miroslav L. <mli...@re...>]

On Fri, Jun 19, 2015 at 07:53:52AM +0000, Chandra Mallela wrote:
> 
> 
> Hi Friends,
> 
> I would like to double-check whether my following interpretation is correct. Please elucidate me.
> 
> For the following ptp4l output, the ptp4l reports rms value and the max deviation from the mean offset. Thus, if I have to report the worstcase accuracy, I take the (rms+max). For example, , looking at the first line, I see that the maximum offset uncertainty/inaccuracy  observed is 2 +7 = 9ns. The maximum frequency uncertainty is (156403 + 7) pbb.

The max value is just the maximum measured offset in that interval. It
doesn't mean it's also the worst accuracy of the clock. There could be
an asymmetry in the network delay and ptp4l wouldn't know the clock is
actually behind or ahead of the time source. To evaluate the accuracy
you would to measure the error independendly from PTP, for example by
comparing PPS signal generated by the synchronized clock with the
reference on a scope.

-- 
Miroslav Lichvar