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TRB500

TRB5_R_00.07.02.8

Hi, after some time, sometimes after few minutes, sometimes after a day, download speed drops and keeps not more than 260Mbps while right after gateway restart I am able to reach 400-600Mbps, the biggest strange here that it is always stays around 250-260Mbps. And it is no matter if it is peak time of the day, or middle night, same situation.

Upload speed is stable and stays at 120-140Mbps all the time.

Signal quality, CA bands and all other signal parameters is pretty the same before and after the restart. Reboot of modem usually doesn't help, only whole gateway restart brings speed back.

Also "Signal quality" is always static number -51, it doesn't change even when snowing.
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Added screenshot and CSV of speed tests with the same server before reboot and right after reboot

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Hello,

Thank you for the detailed report.

I assume, the attached troubleshoot file was made after the download speeds fell. Could you generate and attach one shortly after reboot, while the download speeds are still high?

As for signal quality metrics representation, there are issues in the WebUI in current firmware version, which are solved in the upcoming 7.3 release, thus I would like you to login to the device via SSH and execute the following commands in both instances of download speeds to see if anything differs:

  • gsmctl -A 'AT+QCAINFO'
  • gsmctl -A 'AT+QENG="servingcell"'

Best regards,

by
Troubleshoot file was made after reboot and some speed tests.
Added couple screenshots made at night before (when speeds were lower) and after (speed returned to normal) reboot.

I am using directional antenna, so it doesn't jump between towers, cells also seems to be stable, ID's not changing.

Will make more also with second command when speed gets down.
ago by
Hello,

Do You need any more details or it is enough for now?
ago by

Hello,

Apparently this is a known issue related Qualcomm's Internet Packet Accelerator (IPA), a hardware block performing certain functions without using the main processor, driver's offloading functionality. The algorithm that is being using doesn't work when the throughput gets more sessions than a certain number. Some faulty C++ written ipacm daemon is used, which tracks connections and decides, when to inform IPA driver to offload the sessions, which allows to have proper speeds. On a failure, traffic is forwarded through the CPU and it maxes out at the given speeds of 200 Mbps or so because the SoC CPU is single CORE and it is on the lower performance rate.

The issue is being worked on, however the solution may take a while.