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Date/Time: Fri, 29 Nov 2024 16:31:39 +0000

How to Post a Message for Support

The data feed was lost. There was no activity for at least 60.0 seconds.

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[2015-09-24 11:56:07] #1 [Go To First Post]
vbmithr - Posts: 204
I got this message in SC's log. I don't understand what triggers this, and the disconnection from the service. Heartbeats are correctly answered.

[2015-09-25 20:24:00] #2 [Go To First Post]
DTC Engineering - Posts: 320
It indicates the heartbeat messages are not being received. How often are you sending the heartbeats?

[2015-09-25 20:30:26] #3 [Go To First Post]
vbmithr - Posts: 204
Often enough, and I never got this error before. I think there is a bug at some point in my software such that heartbeats are not received anymore for some reason. Thanks!

[2015-09-25 20:32:19] #4 [Go To First Post]
DTC Engineering - Posts: 320
OK please check, because this indicates Sierra Chart is not receiving a heartbeat during a 60 time span or any data feed activity. You should be regularly sending out heartbeats every 20 or 30 seconds, regardless of whether you get a heartbeat from the DTC client. Date Time Of Last Edit: 2015-09-25 20:32:34

[2015-09-25 20:57:01] #5 [Go To First Post]
vbmithr - Posts: 204
Yeah, that's what I'm doing, normally :)

[2015-10-08 13:57:44] #6 [Go To First Post]
vbmithr - Posts: 204
This was due to a message corruption from my side: Message packing issue. I did not know that a C++ compiler was also padding bytes at the end of a structure to have the end of the structure 8-bytes aligned.

[2015-10-11 21:20:35] #7 [Go To First Post]
DTC Engineering - Posts: 320
Was this a problem with the heartbeat message that you were receiving or the heartbeat message that you were sending? Either way this should not be a problem because the beginning of every message contains its size. And any extra padding at the end should really be irrelevant.

[2015-10-11 21:23:51] #8 [Go To First Post]
vbmithr - Posts: 204
That's the thing, because of lack of padding at the end of a message, the size of the next message was considered by Sierra Chart as the padding at the end of the previous message, and thus SC believed the next messages' type was actually its size…

[2015-10-11 21:38:23] #9 [Go To First Post]
DTC Engineering - Posts: 320
This is the reason why each DTC message contains a size at the beginning. If you set the size of the message to the actual size you are putting into the network stream without the padding, it would not matter. When Sierra Chart is reading messages, it works strictly with the sizes in the data stream. Not off of the sizes in the header file. It is perfectly fine to remove the padding off the end and reduce the size of the message to what you are actually sending. It will not do any harm. So how were you setting the size of the message? Date Time Of Last Edit: 2015-10-11 21:39:16

[2015-10-11 21:43:20] #10 [Go To First Post]
vbmithr - Posts: 204
Yeah, it's strange now you say this. I am 100% sure that the sizes of my messages are correct, i.e. I am sending the size I put in the structure. I need to look in my git tree to figure out what I changed. I can't repro this bug anymore now, but if I can find what it was I'll tell you. Thanks!

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