Time Stability

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dciliske
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Re: Time Stability

Post by dciliske »

Any commentary on whether you're seeing frame loss on maximal length frames?
Dan Ciliske
Project Engineer
Netburner, Inc
SeeCwriter
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Re: Time Stability

Post by SeeCwriter »

dciliske wrote:Any commentary on whether you're seeing frame loss on maximal length frames?
The vast majority of our network traffic consist of packets that are less than 512 bytes. How would frame loss manifest itself? Would I need to have wireshark running to see it?
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pbreed
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Re: Time Stability

Post by pbreed »

Just poor TCP performance and lots of retransmits....
SeeCwriter
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Re: Time Stability

Post by SeeCwriter »

pbreed wrote:Just poor TCP performance and lots of retransmits....
I ran wireshark, and for the last 90-minutes there were no retransmits or connection issues. Comm looks good.
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Re: Time Stability

Post by SeeCwriter »

The second NTP resync occurred while I was at lunch. The values of TimeOffset are:

On bootup: 1495649838
NTP Resync, 1hr after bootup: 1495649836
24hr NTP Resync: 1495649743

Update:
Here's the printout from the serial port. The first NTP resync is 1hr after bootup. The second is 24hrs later. The module is running about 90-seconds fast after 24hrs.

Time From NTP Server: 2017/05/24,11:17:17, 1495649836
Time From NTP Server: 2017/05/25,11:15:44, 1495649743
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pbreed
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Re: Time Stability

Post by pbreed »

Until we can rule out a hardwareefault. (Either that specific module, or noisy power/environment) I'm not sure what else to do.
My rev 1.9 test unit has run 28 hours without loosing a single second....
Dan's and Toms test units have been similar.

Can you swap the unit under test?
Would you like to ship us the unit with clock issues?
Want to purchase a new unit and we will do a 24hr local test here before shipping it to make sure its good....
I can lend you the 1.9 unit and carrier I've been testing (Won't sell it, its been abused on my desk for a year or more)

Paul
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Re: Time Stability

Post by SeeCwriter »

I agree that there's nothing else for you to do. We see this on multiple modules, so I'm convinced the problem is with our hardware. Unless testing determines otherwise, I think we are done here.

Thank you.
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