TCP behavior – data spike – see data every two minutes [on hold]

        I am seeing a strange behavior with a TCP connection. I've a sender which sends data in spikes. After the spike, the receiver starts seeing 1460 bytes every two minutes, even though the sender has already sent all the data. I see that the sender side TCP send queue is large. So the kernel is probably holding onto the data. What could be causing this? Why is it 1460 bytes every 2 mins? Before the spike, the flow is normal. After the spike, the data is received something like this:
(Snippet from application log on recv side) 08:25:29.212692 received 1460 bytes from fd 6 08:25:30.188926 received 1460 bytes from fd 6 08:25:31.313822 received 23360 bytes from fd 6 08:25:31.417442 received 1460 bytes from fd 6 08:25:32.593822 received 1460 bytes from fd 6 08:25:33.132610 received 1460 bytes from fd 6 08:25:34.880063 received 1460 bytes from fd 6 08:25:38.100971 received 1460 bytes from fd 6 08:25:44.997209 received 1460 bytes from fd 6 08:25:57.502490 received 20440 bytes from fd 6 08:25:58.018307 received 154760 bytes from fd 6 08:25:58.697924 received 32120 bytes from fd 6 08:26:00.010289 received 1460 bytes from fd 6 08:26:01.575468 received 1460 bytes from fd 6 08:26:04.330449 received 1460 bytes from fd 6 08:26:10.795441 received 1460 bytes from fd 6 08:26:23.763449 received 1460 bytes from fd 6 08:26:49.620459 received 1460 bytes from fd 6 08:27:41.333464 received 1460 bytes from fd 6 -->starting here we receive data every 2 mins 08:29:24.758463 received 1460 bytes from fd 6 08:31:24.759446 received 1460 bytes from fd 6 08:33:24.760445 received 1460 bytes from fd 6 08:35:24.761450 received 1460 bytes from fd 6 08:37:24.762448 received 1460 bytes from fd 6 08:39:24.763449 received 1460 bytes from fd 6 08:41:24.764465 received 1460 bytes from fd 6 08:43:24.765454 received 1460 bytes from fd 6 08:45:24.766454 received 1460 bytes from fd 6 Note that the number of received bytes is a multiple of 1460. So something related to TCP Max Segment Size? Platform: bash-4.1$ uname -a Linux 2.6.32-696.20.1.el6.x86_64 #1 SMP Fri Jan 12 15:07:59 EST 2018 x86_64 x86_64 x86_64 GNU/Linux

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