Multi-Thread Bandwidth Test Slower than Single-Thread?

Boris_yo

Limp Gawd
Joined
Oct 22, 2011
Messages
224
Hello,

By default Speedtest is configured for multi-thread test but there's also single-thread test. Normally multi-threaded test was showing good results until recently. I checked single-threaded test and now results are like those that I had in multi-threaded test. If you tap on video, on 3 dots you will see option to view in full screen:

I don't understand why. Single-threaded connection shows good speed but multi-threaded connection shows 3 times less initially and then jumps up and stays fluctuating.

My ISP Sagemcom F@ast 3184 wireless router transmits in 2.5GHz, channel width 20MHz, WPA2 encryption to Edimax BR-6428nS v2 wireless router (repeater mode).
 
Also, I have TP-Link TL-MR3020 travel mini router configured in WISP mode and I don't see those fluctuations. Only in repeater mode.
 
First and foremost, you should only test wired to have consistency if you're trying to diagnose your isp. If you know the isp is okay, you can use speedtests to try to diagnose wireless issues, but most of us use iperf for that.

For testing, I've never found speedtest.net to be reliable. I use dslreports.com/speedtest and fast.com as they seem to be accurate across a wide variety of isps (I deal with 4x isp accounts with 3x providers).
 
Are you testing form the main WiFi or from the repated one? If so, you might be creating your own traffic to compete with yourself. There is a lot to factor in with wireless and repeated networks add on to it.
 
We're you looking at the units? They're in KBs, not MBs.

Also I don't know where people are and what relative connections are like.
I read that with a big sarcasm filter, as those speeds are abysmal.
 
Don't feel too badly, when I was looking at it I was confused and then I saw the units.

Still I wish I had more of an answer.
 
First and foremost, you should only test wired to have consistency if you're trying to diagnose your isp. If you know the isp is okay, you can use speedtests to try to diagnose wireless issues, but most of us use iperf for that.

I can test with wired connection but if there's wireless transmission issues between ISP's modem and my repeater I won't be able to determine that.

My PC is connected wiredly to ISP's modem and there were no issues with it.

Are you testing form the main WiFi or from the repated one? If so, you might be creating your own traffic to compete with yourself. There is a lot to factor in with wireless and repeated networks add on to it.

Both and alsobI tried connecting second repeater to first repeater for troubleshooting purposes. Yet I still experienced disconnections. Too bad my ISP's modem log functionality doesn't show details of disconnections.

How does traffic compete with repeater?
 
I mean traffic competing with yourself. I'm a little confused on your network but it seems that you have a modem/router from your ISP then an Edmax that connect to it via wifi but then wireless connects to other APs in a mesh? Then you have clients on various points on that Edmax mesh.

What I mean by competing with yourself is that wireless adds things to consider on top of a regular network. I've done multiple transfers over wireless and not had them equal the throughput of a single transfer. You're going to have a little overhead per connection anyway (though it shouldn't much). I can't test this and have read anything on it, I have the though that if you're maxing out your connection with multiple connections you might get to a point of diminishing returns. Latency is going to go up as things are squeezing through that pipe. I don't know the airspace around you and how your repeating is setup, but it could be that they are "stepping" on each other depending on what bands they are using. The uplink seems to be low too, and if the mesh is faster than that, there is going to be some rate limiting and buffering that needs to happen when connecting through it. Which in theory should just slow everything down to that speed through it but in reality could also add a little more congestion too.

I think I had more to say or wanted to correct stuff but I was writing this yesterday and got swamped and I'd take too long to rewrite it.
 
I don't know the airspace around you and how your repeating is setup, but it could be that they are "stepping" on each other depending on what bands they are using.

Repeaters use same 2.5GHz band and same channel of the source. Each repeater just propagates source's signal. I would change this but it's now possible. I just wanted to repurpose old routers I have because there's no point in buying new router having 200/5 bandwidth speed.
 
Repeaters use same 2.5GHz band and same channel of the source. Each repeater just propagates source's signal. I would change this but it's now possible. I just wanted to repurpose old routers I have because there's no point in buying new router having 200/5 bandwidth speed.
Generally a repeater ends up halving the bandwidth because it is using the same. Do this a few times and you can kill even strong bandwidth when you factor in additional losses from being wireless.
 
SamirD Why this doesn't apply in a scenario when I have neighbors sitting on the same band and channel? Aren't they competing with me?
 
SamirD Why this doesn't apply in a scenario when I have neighbors sitting on the same band and channel? Aren't they competing with me?
They are competing too, but generally the strength of neighbors signals won't be as strong as your own and as far as repeaters go, they are halving the bandwidth because they're essentially having to receive from the source AP and pass it on using the same wireless hardware (the nitty gritties aren't exactly like this, but it basically works this way).

So while a neighboring signal may interfere with yours, a repeater even in ideal circumstances will be halving the bandwidth as it passes the signal on.
 
Sorry I didn't get notices for these updates like SamirD said it all counts.

Think of it like sound, say you're in the gym, and they are playing music but you've got headphones on listening to your own music. You can still hear theirs but what's on your headphones drowns them out may not hear whispers (Like the very beginning of the song Roxanne by the Police, someone hits some piano keys and there is a laugh) but you'll still enjoy your music. That's you and your neighbors. Then lets say your in a store and they're playing music, then someone walks in playing music on their cellphone loudly. You can still hear what's on in the store but the cellphone music is annoying, you may miss some of the words in the mall music. The closer the cellphone gets to you, the worse the annoyance gets.

Same with WiFi, but we're talking about specific frequencies and overlap, not a bunch at one time. You also have to factor in that this two sounds source analogy happens both ways. From the access point to the device and in reverse as well.
 
SamirD bigstusexy Have been testing for several hours and I am confused now.

First, here is a diagram of Wi-Fi access points:

Screenshot_20211211-095940_WiFi Analyzer.jpg


(1) Unavailable - ISP Modem/Router (PC room)

(2) TP-Link_POCKET (WISP Mode, 2 doors and 7 meters away from PC room)

(3) Unavailable1 (Repeater Mode, 2 doors and 7 meters away from PC room)

All 3 devices are on the same 13th channel.

- Connecting smartphone to (1) from 30cm range gives me 6 - 7 MB/s

- Connecting smartphone to (2) from 10cm gives me 3 - 3.5 MB/s

- Connecting smartphone to (3) from 10cm gives me fluctuating rate between 1 - 2.5 MB/s (FYI: when testing multiple connections, the speed dives to 150 KB/s right away and slowly picks to 2 MB/s. Single stream is stable at 2 MB/s with no fluctuations.)

Now here's what boggles my mind - connecting smartphone to (3) using USB to Ethernet converter gives me a whooping 10.5 MB/s!

- How is it possible that (1) from 30cm that gives me 6 - 7 MB/s wirelessly gives 10.5 MB/s to (3) from 2 doors and 7 meters away?

- How is it possible that (3) gives me 2.5 MB/s wirelessly from 10cm range while using wired connection it gives me 10.5 MB/s?

It's can't be because all 3 devices compete for 13th channel, can it? If it was the case I would not get 10.5 MB/s from (1) to (3).

I don't understand what's going on...
 

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The usb to ethernet converter is a clue--at 10Mb/s, you're being limited to 100Mbs network speed. I'd check all the access points/repeaters to make sure they're gigabit.
 
SamirD ISP modem is Gigabit and 802.11n but the rest are 100MBps and 802.11n which is fine.
Why do I get 6 - 7 MB/s from ISP modem very close while getting 10.5 MB/s from ISP to repeater which is 7 meters and 2 doors away?
Why when very close to repeater I get 2.5 MB/s wirelessly but when connected to it wired I get 10.5 MB/s?
I should be getting half of 10.5 MB/s wirelessly from repeater.
 
SamirD ISP modem is Gigabit and 802.11n but the rest are 100MBps and 802.11n which is fine.
Why do I get 6 - 7 MB/s from ISP modem very close while getting 10.5 MB/s from ISP to repeater which is 7 meters and 2 doors away?
Why when very close to repeater I get 2.5 MB/s wirelessly but when connected to it wired I get 10.5 MB/s?
I should be getting half of 10.5 MB/s wirelessly from repeater.
Hmmm...you should be getting more from the isp wireless if your device is capable--remember, n was an 'in-between' spec before ac was announced so implementation was all over the place. What I would try is wired to the isp modem and see what you get there and then we can see what happens.

But I wouldn't expect much from 100Mb bandwidth. It was rare to see100Mbs support the full 10MB/s, even back in its hayday. The best I ever saw out of 100Mbs back then was around 8MB/s and realistically is was more like 3-5MB/s--and this was with wired systems in that era. Today, I think it's possible to get close to 90Mbs, but only with testing and in ideal situations (wired iperf).
 
Seems like maybe your wireless "backhaul" is working fine but maybe the wireless on your phone isn't? The TP link and the repeater seem to be close to each other and the way it's drawn they both connect directly back to the ISP modem. Is there a need for the TP link one?
 
What I would try is wired to the isp modem and see what you get there and then we can see what happens.

When I connect PC using LAN cable to ISP modem (100/1000 LAN) I get around 23MB/s (I have 200/5 Mbps subscription package)

When I connect smartphone or tablet to ISP modem using 10/100 LAN USB to Ethernet adapter I get around 9.5 - 10MB/s.

Seems like maybe your wireless "backhaul" is working fine but maybe the wireless on your phone isn't? The TP link and the repeater seem to be close to each other and the way it's drawn they both connect directly back to the ISP modem. Is there a need for the TP link one?

I get same speed on tablet too... I haven't tested with laptop though... I use TP-Link in WISP mode because it doesn't disconnect from ISP modem like it does when configured in repeater mode as well as my Edimax wireless router in repeater mode. Edimax doesn't work in WISP mode.
 
Okay, seeing your other post. If you can wire things, why not go that route?

Even if you aren't using any kind of advanced setup I'd go that route

ISP <-->Edmax
|
|<--> Repeater (if needed)

Connect a lan port of the router to a lan port of the Edmax/Repeater, turn off DHCP on those last two.
Then on those use a different wireless network name and non-overlapping channel. Put all profiles in the client devices. Done

The only bad thing is you aren't going to get and "steering" if you on a network but technically another one is a bit better, it's up to the device to decide to switch.
 
bigstusexy SamirD I didn't mention but after a week or so, when my Edimax wireless router is set to AP mode it slows down to 2.5 MB/s and I cannot get to its administrative management interface. Entering IP returns error in browser. So I hoped that with Repeater mode it won't happen but I experience disconnections in that mode on both Edimax and TP-Link router.

I am just very curious how on my ISP modem I get 6.5MB/s wirelessly but with Edimax in Repeater mode and Wi-Fi Bridge mode when connected with cable, I get 10.5MB/s in another room, 7 meters and 2 doors away. If my Edimax worked well and didn't slow down, I would not go down the rabbit hole but I took the red pill and must find the truth. If my TP-Link was 300Mbps I would use it as a fallback but it's 150Mbps which kind of explains 3MB/s speed I get from it wirelessly which is 24Mbps and only 1/6 of 150Mbps...

I found more wireless options under Advanced options and am wondering if I can do something to improve wireless speed of Edimax in Repeater mode so I can get at least half of 10.5MB/s it gets from ISP modem and not 2-2.5MB/s like I currently do for unclear reasons.

Data Rate has options ranging from 1M up to 54M. Currently set to Auto.

N Data Rate has options ranging from MSC0 up to MSC15. Currently set to Auto.

Screenshot_20211219-054045_Chrome.jpg
 
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I've not done too much with direct settings like this, mostly setting the channel width, and power, but the last was for vastly different situations.

If you you're saying:
ISP <wireless> 6.5MBps
ISP < wired > Edmax <wireless> 10.5 MBs
ISP < wireless > Edmax <wireless > 2.5

Well your problem is the ISPs wireless.
 
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