[Rocketboy235]

Hello,

So I have been experiencing some inconsistent WiFi speeds while using my EA8500 with DD-WRT for some time now. This has existed in previous builds and still exists to this day. Originally, I thought if I do a full factory reset and clear the nvram, my problems might go away. Unfortunately, that did not happen. Scratching my head over here trying to figure out why this is happening exactly and what would be the appropriate solution.

Issue
My download speed over WiFi on the 2.4 GHz network is abnormally low (usually hovering around 5 mbps while upload appears to be normal).

The download speed on the 5 GHz network is not bad, clocking in around 100-120 mbps.

Upload speed limit is only 6 mbps and there is little variation so I'm going to assume upload is mostly okay.

I first noticed this when I ran speed tests and then saw that the 5 Ghz has an issue where the speeds start off as fast and then sometimes (not all the time), drops down to 0.5 Mb/s.

I do not have an issue for the most part when I transfer files locally so mostly just an internet thru wifi issue.

I'm not sure if maybe I have a QoS issue? I currently do not have QoS on and it is only the 2.4 GHz network that is slow.

You can skip the stuff below but if you are curious as to what I did before I posted here, read on.

TL;DR for tests ran - local transfer speeds are okay and not really affected so really it's just only the internet download speeds that seem to be strangely slow. There was a case where I did a file transfer while doing a speed test and I noticed during the speed test, the file transfer dropped to a 1-2 Mb/s instead of 30-40 Mb/s over 5 GHz WiFi.

Strange Occurrences
Ran a speed test while transferring a large file over Windows network drive and saw that the file transfer speeds severely dropped during the download portion of the speed test.

When I restricted the access on 2.4 GHz network (different wifi password), I noticed for the first few minutes, when I did a speed test with only 1 device on the 2.4 GHz network, I was able to get nearly max D/L speeds of 120 mbps download. After a few minutes, it goes down to 3-5 mbps D/L again.

----------------------------

Tests Ran

* Ran a speed test (DSLReports and Ookla) on my home server which is connected via Ethernet and I always hit the advertised download/upload speeds so Ethernet is not a problem. Looks to be only a WiFi issue.

* I have numerous pictures when I ran these tests but because I have so many and I'm not sure how helpful they may be, I'll show some but majority of them will only be provided upon request. Will be provided in 2nd post of this thread.

* Clients used for testing:

Windows 10 Desktop with USB 802.11n AC (AWUS036AC) Dual Band [up to 867 Mbps]

iPhone SE (2016 Model)

* Disclaimer: Not the most scientific tests and there are some variations/factors that come into play such as network load when other devices may be using the Wifi which may affect performance during my testing.

WiFi SweetSpots
Not sure if a great test but at least I can test the transmission speed from client to router (doesn't test the transmission speed from router to client however it seems).

In this test scenario, I did the test standing a few feet from the router with my iPhone SE and was in direct line of sight. I also did another test where I was about 20 feet away from the router but in another room (and separated by 2 walls). We'll call this Room A.

* On 2.4 GHz, I was able to get 100-110 mbps from Room A. Was able to get roughly same speeds when I stand next to it as well.
* On 5 GHz, I was able to achieve 200-300 mbps from Room A. Was able to get 500 Mbps when standing just a few feet away. No issue here.

Internet Speed Tests

Ping has been mostly consistent so far in all of these tests. ~10-15 ms - Did the test on my Desktop

* Day 1:
Ookla
2.4 GHz: 24 mbps D/L, 6 mbps U/L
5 GHz: 120 mbps D/L, 6 mbps U/L

DSLReport
2.4 GHz: 3 mbps D/L, 2.5 mbps U/L
5 GHz: 120 mbps D/L, 5 mbps U/L

2nd Test:
2.4 GHz: 5 mbps D/L, 6 mbps U/L

* Day 7:
Ookla
2.4 GHz: ~5 mbps D/L, ~5 mbps U/L
5 GHz: ~5 mbps D/L, ~5 mbps U/L

It seems the AC WiFi somehow messed up and internet slowed to a crawl when the router was only restarting the WiFi radios (not the whole router). It was fixed after restarting the WiFi radios again.

Ookla
Retest - 2.4 GHz: 4.4 mbps D/L, 6 mbps U/L
Retest - 5 GHz: ~90 mbps D/L, 6 mbps U/L

DSLReport
2.4 GHz: ~2.3 mbps D/L, ~1.6 mbps U/L
5 GHz: ~2 mbps D/L, ~3 mbps U/L (download speeds were close to ~90-100 mbps initially and then quickly dropped to 3 mbps)

iPerf3

Set up a iPerf server on my home server and also on my main computer (took turns sending data back and forth).

Used the "-w 16777216" parameter for iPerf3 to test full speed

* Day 1
2.4 GHz:
~85 Mbps

5 GHz:
~400 Mbps

* Day 7:
2.4 GHz:
~65-70 Mbps

Windows File Transfer over Network

* Shared a 5-6 GB file over Wifi and looked at the speeds.
* Transferred a file from my desktop over to the home server

* Day 1:
2.4 GHz: ~10 Mb/s (80-90 mbps)
5 GHz: ~50 Mb/s (400 mbps)

* Day 6:
2.4 GHz: ~8 Mb/s (60-70 mbps)
5 GHz: ~30 Mb/s (240 mbps)


Some information regarding my network configuration/setup:

* EA8500 Router (had DD-WRT on it for 2+ years now)
* Home server and VoIP phone system are connected to the router via Ethernet
* About 20 devices connect to the WiFi (roughly 60% on 2.4 GHz while 40% are on 5 GHz. All devices have 802.11n or 802.11ac and nothing older.)
* did a factory reset of DD-WRT recently and installed latest BS Build at the time (r43171 5/16/2020).
* My WiFi network settings should match what MSOEngineer has posted in his signature
* Comcast Xfinity ISP
* Download Speed: 120 mbps
* Upload Speed: 6 mbps

Thanks in advance and let me know if I miss any information. Sorry for going a little overboard here but I wanted to try to test and hopefully narrow down the issue before reaching out for help here.

[Rocketboy235]

Links to Images here:

Speed Tests:
https://imgur.com/a/UUtyABB

Wifi Settings:
https://imgur.com/a/czXgJHs

Other images showing Download Speed Issue:
https://imgur.com/a/cuOmZJf

[blkt]

Well, speaking from a builds perspective I experienced the best 2.4 GHz performance on those following after r43171.

I know mrjcd has recommended r43192 as a fallback build, and personally for me r43209 and r43217 speeds were outstanding.

Currently I'm on r43334, but have yet to reach the same speeds as the above mentioned builds from a few weeks ago.

Builds from this past week I experienced a latency issue; refreshing time.is could not achieve below ±0.010 second accuracy.

Running around in a quake session ping and player lag wasn't very stable, but with r43334 I'm not having either of these issues.

[Rocketboy235]

I could give the newer builds a try. I remember having this same speed issue on the previous BS build as well (November 2019). Cannot remember if I had this issue on a Kong build but maybe.

I also quickly tried out QoS but that didn't seem to have any effect at all.

It appears that my 5 GHz network is now acting up and when doing a speed test, I get a pitiful 5 Mbps D/L. Very strange to see that when I do a network file transfer inb addition to downloading a large game from steam (right now it's downloading it at ~400-600 kb/s), the Windows file transfer speed fluctuates between 1 and 3 Mb/s. When I pause the steam download, the network file transfer shoots up to 40-50 Mb/s as it should be. When I resume the steam download, the file transfer speed falls back to 2 Mb/s.

I wonder why the 5 GHz network was fine and then later, it messes up... hmm...

I may need to do a test where I only have 1-3 clients connected and slowly add one by one over a few days and observe the network.

Edit: Forgot to mention but I also performed a speed test on many other devices, and got similar results of low download speeds.

[servicetech]

[blkt]

[servicetech]

[tatsuya46]

[servicetech]

[Chronoscape]

Try turning off Airtime Fairness, that tanked the 2.4ghz band on my EA8500.

[msoengineer]

[Rocketboy235]

Thanks for all of the input guys!

I did do a nvram erase and updated the build very recently but I guess it's possible that there may still be issues that could occur during flashing.

I decided to try the easiest recommendations first just to see what would happen and it seems that when I turned off Airtime Fairness (so far only for the 2.4 GHz), the network speeds are showing my typical download speeds!

It could be that some devices on my network are causing trouble and is messing with the Airtime Fairness of the router?

Anyway, I will still go ahead and update my firmware as suggested in this thread and try it with Airtime Fairness off and then on very soon. Also interested in trying the Protection mode setting but maybe it's just the Airtime Fairness.

Thanks again guys and stay tuned. Going to update this thread with my results when I upgrade the firmware.

[Rocketboy235]

Hello,

So I got build 43420 installed and so far, it's been doing pretty well. I decided to have Airtime Fairness left on and observe the Wifi behavior.

I do notice the download speeds drop to 3-5 Mbps sometimes but it will go back to usual regular speeds. Speeds are not always consistent.

After a few more days, I will turn off Airtime Fairness and observe the behavior and see if there is any substantial difference.

Overall, much better than before but still room for improvement! Also, not sure if it's just me, but I noticed the local network file transfer speeds seem to have degrade a bit for the 5 GHz network. I was getting ~30 mb/s instead of 40-50 but that could be due to some other factors. Will need to check.


UPDATE: I noticed that once in a while, websites I am trying to access would take a long time to load while on my Desktop connected via 5 GHz. When I checked on my phone (connected at 2.4 GHz), it was able to load the web pages fine. I then connected to 5 GHz with my phone and then proceeded to load a webpage and only then did my desktop finally load the webpage. Coincidence?

[servicetech]

[stephensuley]

I have the EA8500 and have been struggling with the same issue.

I power cycle it and the 2.4Hgz will work as expected, until it slows down again after X # of hours.

I used that 43192 build and then followed msoengineer QCA wifi guide. msoengineer said that build is rock solid. After 5 days we still observe the issue at least once daily. All wl0 devices are impacted, until I reboot router.

The 5Ghz doesn't have the issue.

I came to the forum today to post about it and get help, and I found this at the top of board.

Router Name: ea8500
Router Model: Linksys EA8500
Firmware Version: DD-WRT v3.0-r43192 std (05/19/20)
Kernel Version: Linux 4.9.223 #546 SMP Mon May 18 02:17:06 +03 2020 armv7l




Clients within my environment
I have ~12 wl0 clients and 3 wl1 clients;

Iphones,ipads,iWatches lenovo laptops,dell desktops, apple TV, 3x google homes, netatmo weather, netatmo security, Philips HUE, A couple of Dyson fans.

I also have a client bridge mode rt-66u connected to the EA8500 for my Cisco lab gear in my office.