Slow download speed: Netgear R7800 Nighthawk X4S

[Foil64]

Hi, I'm brand new to OpenWRT and this is my first time installing it on a router.

My ISP claims my maximum download speed is 1000Mbps.

Before installing OpenWRT, my wired (ethernet) download speed was pretty close to that, at approximately 975Mbps.

I just installed OpenWRT 22.0.3, r20028-43d71ad9e, and my speeds were:

Wired: 300Mbps
Wireless (5GHz): 75Mbps

After doing some reading, I enabled software flow offloading, and that increased my speeds:

Wired: 575Mbps
Wireless (5GHz): 250Mbps

Any suggestions for troubleshooting slow speeds? Also, for those of you who have the same router, I'm curious to know, what kinds of download speed are you getting for wired and wireless?

Here is my wireless config. Let me know if there's any other info I can provide that might be helpful. Thanks in advance.

-----------------------------------------------------
 OpenWrt 22.03.3, r20028-43d71ad93e
 -----------------------------------------------------
root@OpenWrt:~# cat /etc/config/wireless

config wifi-device 'radio0'
	option type 'mac80211'
	option path 'soc/1b500000.pci/pci0000:00/0000:00:00.0/0000:01:00.0'
	option channel '36'
	option band '5g'
	option htmode 'VHT80'
	option cell_density '0'
	option country 'US'

config wifi-device 'radio1'
	option type 'mac80211'
	option path 'soc/1b700000.pci/pci0001:00/0001:00:00.0/0001:01:00.0'
	option channel '1'
	option band '2g'
	option htmode 'HT20'
	option cell_density '0'
	option country 'US'

config wifi-iface 'wifinet0'
	option device 'radio0'
	option mode 'ap'
	option ssid '<redacted>'
	option encryption 'psk2'
	option key '<redacted>'
	option network 'lan'

config wifi-iface 'wifinet1'
	option device 'radio0'
	option mode 'ap'
	option ssid '<redacted>'
	option encryption 'psk2'
	option key '<redacted>'
	option network 'guest'

config wifi-iface 'wifinet2'
	option device 'radio1'
	option mode 'ap'
	option ssid '<redacted>'
	option encryption 'psk2'
	option key '<redacted>'
	option network 'lan'

config wifi-iface 'wifinet3'
	option device 'radio1'
	option mode 'ap'
	option ssid '<redacted>'
	option encryption 'psk2'
	option key '<redacted>'
	option network 'guest'

[slh]

The nbg6817 is basically the same hardware as your r7800, so the same background applies:

Bandwidth Issues on Zyxel NGB6817

Hi All, Brand new to this and complete n00b. Started messing around with my Zyxel NGB6817. I got OpenWrt installed and setup with Luci and a few other basics. I'm having a few issues getting max performance. I have 1GB up and down, confirm at the modem. I configured a few things including Software Flow Offloading, Hardware Flow Offloading, Irqbalance, and set the CPU govenour to performance. All based on other recommendations I found. I'm still seeing my up and down closer to 100MB (up to ab…

While I would expect a (wired) throughput of around ~550-650 MBit/s (well, you don't say anything about your WAN configuration, if you need PPPoE, ~300 MBit/s might be reasonable), it won't do anything close to 1 GBit/s.

So you have 500Mbps-1Gbps fiber and need a router READ THIS FIRST

It's such a frequently asked question over the last few years that we really need a post we can point people to. So your cable company rolled out 500Mbps or 1Gbps download speeds, or you have 1Gbps symmetric fiber (GPON/EPON) from ATT or Centurylink or Orange or whoever. You realize your old all in one router from 2009 is not up to the task of handling this, but hey by now stuff should be cheap and available that will handle your new fiber connection right? So you want advice about a router for…

The WiFi performance is a bit harder to judge, without knowing a lot more about your environment (congested environments with many concurrent neighbouring APs will produce more interference -the airtime simply being exhausted- than rural areas where you might not even see your neighbours' houses), nor do you tell anything about the test distance or the clients used for these tests. Most clients (notebooks, phones) will be 2x2 at best, providing you with a (theoretical, not achievable in practice) link rate of 866 MBit/s - under these circumstances, the best you will get out of it in practice will be around ~300-350 (400, if you're very lucky, but neither would ~250 be anything to complain about with lower end clients) MBit/s. 75 MBit/s sounds a bit as if your client would opt to use the 2.4 GHz band, for which there may be several reasons (keep in mind that 5 GHz will take longer to come/ get found by clients, clients may be sticky, etc. pp.).

Always check wired(-only) performance first, if you're in doubt about your router's performance or potential issues with your WAN connection.
At least for the initial WiFi performance testing, avoid complex (multi-vAP) configurations, while those should not cause this amount of throughput loss, there will be some - and the additional interfaces will also delay the interface coming up as well (sticky clients).

[Foil64]

Thanks for the reply.

Some more info: My cable modem does not use PPPoE.

Based on the thread you linked, it sounds like the best performance can be had with a multi-device setup, rather than an all-in-one.

I have a spare Raspberry Pi4 w/ 4GB RAM. If I use that as the router, and my Netgear as a wireless access point, then all I would need is a switch, correct?

What should I be looking for in a switch? Do you recommend a managed switch vs un-managed? Any other specs?

[slh]

I would strongly suggest a USB3 ethernet card[0] for the RPi4[1], to act as dedicated WAN interface, as that massively eases the configuration of your setup[2]. Technically the r7800 can act as L2-managed 5-port switch as well (at no additional performance cost), but (dedicated-) switches are often more convenient. Personally, I prefer (smart-)managed switches these days (and there are quite a few OpenWrt supported ones, even rather cheap on the second hand markets), but technically you can rope in the r7800 for this task - with unmanaged switches behind the VLAN distribution done on the r7800.

From personal experience, I'd also suggest to look for devices like these (the ones raised in the later parts of that thread, not the first AMD Jaguar based ones):

Tips for getting cheap used x86-based firewall with full Gbit NAT (a PC Engines APU) if you are in the US

While I was watching for old stuff I could play with on ebay I noticed that a few sellers are offering a few "cloud managed routers" (i.e. if you don't pay a subscription they are paperweights) from a company called "simplewan" that looked oddly familiar. here some pictures (from auctions, not mine) they are bright orange. [simplewan 3] [simplewan2] [simplewan 1] The images are a dead giveaway, these devices seem to just be a branded version of PCEngines APU1 (the ones with black USB 2.0 p…

The r7800 still is a very decent 802.11ac/wave2 AP (although 802.11ax APs can achieve 700-800 MBit/s (at 2x2) in comparison).

--
[0] USB3 required (not USB2); realtek r815x based ones (starting around ~15 EUR/ USD) seem to be preferred by RPi users, as they tend to be faster and more reliable than their ASIX AX8817X competition.
[1] the RPi4 can easily cope with these WAN speeds, they are just hard to get these days and overpriced.
[2} and this is also be required to really get 1 GBit/s full duplex, rather than 'just' half-duplex a "one-armed router on a stick" can provide.

[mmstano]

Stock OpenWRT doesn’t use the NSS cores to their maximum potential. A custom NSS build has been made for the ipq806 processor that the R7800 uses and it can achieve the 1gb speeds. See here.