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R7800 high load

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@Voxel Thanks.
I've used telnet for the last weeks cause I just didn't have enough time to configure ssh access. Now I've set up ssh and logged in and it's a different story. I've always used ssh tunneling to access routers and internal LAN network devices. Is the ssh configuration going to survive a firmware upgrade.
View attachment 31464

My experience has been that a firmware upgrade will wipe out the ssh configuration. It takes a few seconds to manually recreate.

Another good alternative to PuTTY is Git Bash, included in the Git software downloadable at https://git-scm.com/download/win
Git Bash provides UNIX command-line tools, including SSH
 
@Voxel Thanks, I have a backup of the public and private keys.
Can you or anyone else explain the %CPU0 and %CPU1 values before and after the slash symbol. Are these readings for the dual-core Qualcomm® Krait™ CPU (1.7 GHz) load only or they show the load of the dual-core 800 MHz Network Subsystem (NSS) Accelerator either.
I still try to understand why sometimes I have relatively high CPUs load (Mostly the value/s after the slash are high. Maybe these are for the NSS?). That high load is observed mostly when I have a torrent client program running (idling) on one Windows 10 PC. The top-procps-ng doesn't show the process responsible for the high load. Maybe the top-procps-ng doesn't show the NSS load.
Screenshot (206).png
 
Can you or anyone else explain the %CPU0 and %CPU1 values before and after the slash symbol. Are these readings for the dual-core Qualcomm® Krait™ CPU (1.7 GHz) load only or they show the load of the dual-core 800 MHz Network Subsystem (NSS) Accelerator either.
I believe that it is for each core, not showing NSS acceleration activity.
 
Values after "/" are system/kernel times.
You add the values before and after the "/" to get the total - as the bar is showing.
So is there a way to understand what system/kernel is doing at that time. For the addition and the bars it's easy guess.
 
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I do not quite understand you guys... Nothing new. This top is usual for me so it is why I added it to firmware. I am using Debian to compile firmware and its top is the same:

1614868583816.png



The same is with 'ps-procps-ng' vs 'ps' from busybox. I type the command ('ps') automatically, so just automatically I type:

Code:
ps aux

instead of just 'ps'. And I see more advanced:

1614868831338.png


So it is why my /root/.profile is:
Code:
#!/bin/sh

alias ps='/usr/bin/ps-procps-ng'
alias top='/usr/bin/top-procps-ng'

export PATH=/opt/bin:/opt/sbin:/bin:/sbin:/usr/bin:/usr/sbin

'alias' is very useful. When now I type 'top' I have: '/usr/bin/top-procps-ng'. When 'ps aux' I have '/usr/bin/top-procps-ng aux'

Just as a hint...

Voxel.
 
No complaints here.
I'm using Debian too for compilation of OpenWRT firmwares. I was just trying to understand why there are no relevant values for CPU load on the rows below the %CPU0/CPU1 when the CPU0/1 values on top were around 40-50%. I thought if it is possible to monitor NSS load too. Obviously it isn't.
@kamoj ps2 and top2 doesn't work from telnet session in case anyone tries to run them. Via SSH both run as intended. I have configured SSH session that runs top2 immediately after logging with private key from Pageant.
 
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To all interested users and developers willing to help resolve this. @Voxel @kamoj @HELLO_wORLD
I continue this thread with my investigations of the high CPU load of R7800.
After spending over a week trying to figure out the reason (really tricky) for the high CPU usage I think I finally made it.
The situation was described in my previous posts here, here, here and several other posts here.
Disregard all my previous doubts and probable reasons (torrents, DNSCrypt, etc.) I've suspected before.
I have the following network setup. First LAN port of the router is bridged (for IPTV using VLAN and LED blinks in orange). A LAN cable is going to a switch where I have two IPTV set-top boxes connected. I have a PC connected to LAN port 4.
I usually have this normal CPU load when both IPTV set-top boxes are turned off.
Screenshot (209).png


The picture changes to this when one or both IPTV set-top boxes are turned on. Below is the minimum load that I was able to capture.
Screenshot (208).png


Next depending on the combination of the TV channels being watched simultaneously (HDTV, FullHD or Standard resolution TV) there are different CPUs loads.
Screenshot (211).png


The worst case supposedly is when 2 FullHD TV channels work simultaneously. From the second picture with 21%/21% load and above I'm unable (always) to open Top command from @kamoj add-on.
With load close to 70-90% it becomes difficult/impossible to open the kamoj Information page too and all negative impacts on the work of the router reported earlier.
Screenshot (213).png


What I have tried so far.
First of all I've thought the bridging is somehow (due to a bug) not hardware offloaded by NSS. In the document here it's written that
NSS acceleration model
• Features
• Designed for Home Gateways (CPE)
• Flow detection based “All-or-nothing”
offload
• Acceleration supports:
• IPv4, IPv6, NAT, PPPoE, L2TP, VLAN, Qdisc

• Performance gain
• Linux: 640k pps (bridged) – 220kpps (routed)
• NSS: 7200k pps (bridged) – 7200kpps (routed)
• 11x (bridged) – 32x (routed)

• Functional behavior
• 0% cpu load seen in Linux
• Keep Linux counters up to date
• Does not require functional changes at an
upper level (user space)
That's why I decided to connect my PC to the first LAN port (disconnecting the cable to the switch) and see what would happen. My Internet provider gives five public IPs that I can use. The PC got a public IP from the ISP via DHCP on the bridged port (now the LED blinks in white). Then I've run several speed tests while I was monitoring the load on my Phone with ConnectBot (my connection is 512Mbps down/150Mbps up) but the CPU load remained low as on the first picture.
The bitrate for one IPTV set-top box is fairly low - maximum of 10Mbps per HDTV channel and only 4Mbps for standard resolution channel (ISP uses HEVC H.265 for data compression).

Second, I've tried to disable DNSCrypt and later Aegis @HELLO_wORLD (thinking it may interfere somehow). With these disabled I have the same high CPU usage when IPTV set-top box/es work.
I still didn't have enough time to try the next things that are in my mind.
I hope someone has good suggestions or maybe similar setup with IPTV (VLAN) and can make same experiments.
Sorry for this long post but using the router this way is not very healthy.
 
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First, nice job narrowing it down to the IPTV boxes. That is a progress, and was tricky.

How is your WAN setup? Do you have a modem or are you directly connected to the ISP with the R7800?

The system load shows that for some reason the data bridged to your IPTV boxes are not fully accelerated. Something is hitting the kernel hard. Maybe installing netdata via Entware could help a little to narrow this further down.

Might not be related, but just in case: https://www.snbforums.com/threads/igmpproxy-r7800-voxel1-79-kamoj1-53-b25-isps-iptv-box.65717/

Another interesting thread (possibly related, but no real answer): https://www.snbforums.com/threads/netgear-x4s-r7800-did-i-hit-a-cpu-bottleneck.50412/
 
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I hope someone has good suggestions or maybe similar setup with IPTV (VLAN) and can make same experiments.
Sorry for this long post but using the router this way is not very healthy.
Thank you for your post. Interesting. Unfortunately I do not have IPTV to test myself.

Well. You are SPP master. Does it mean that you dealed in past with SPP? Are you developer? Do you know C/C++?

What about use of igmpproxy from Entware for your IPTV?

Thank you,
Voxel.
 

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