EAP225 - Wifi performance initally fine then pitiful for some clients

Hi all.

I just got 1Gb Fibre to my property having only had 15Mb ADSL before (woot!).

I've upgrade the firewall (running pfsense) but bottleneck is now the wifi. So, I wanted to upgrade my 2.4ghz wifi to 5ghz. I've CAT5 running round the house but a Linksys WRT1900ACS doesn't reach all the rooms with it's 5ghz. So I looked around and bought some TP-Link EAP225s: 2 indoor V3's and an outdoor, to cover the whole property running as simple APs.

Had been using OpenWRT on the old 2.4ghz devices for years and wanted to carry on. The WRT1900ACS runs OpenWRTgreat and all my wifi devices get a constant >500mb/s on internet speed tests.

But the EAP225 maxes out at 200-250 for most clients. I can live with this, however for some devices (Samsung Galaxy S7, a Dell Precision M4700) I'll get around 150mb/s for the first few seconds but after that it'll drop to about 15mb/s and stay that way until i disconnect and reassociate.

Any ideas how to troubleshoot? It's OpenWRT 21.02.1, i've tried all three alternative ath10k driver packages but no difference.

Some system logs:

Thu Nov 18 09:07:39 2021 kern.info kernel: [322180.772690] ath10k_pci 0000:00:00.0: mac flush null vif, drop 0 queues 0xffff
Thu Nov 18 09:07:39 2021 kern.warn kernel: [322180.782320] ath10k_pci 0000:00:00.0: peer-unmap-event: unknown peer id 0
Thu Nov 18 09:07:39 2021 kern.warn kernel: [322180.790354] ath10k_pci 0000:00:00.0: peer-unmap-event: unknown peer id 0
Thu Nov 18 09:07:40 2021 daemon.notice hostapd: Configuration file: /var/run/hostapd-phy0.conf (phy wlan0) --> new PHY
Thu Nov 18 09:07:42 2021 kern.warn kernel: [322183.986125] ath10k_pci 0000:00:00.0: 10.4 wmi init: vdevs: 16  peers: 48  tid: 96
Thu Nov 18 09:07:42 2021 kern.warn kernel: [322183.993995] ath10k_pci 0000:00:00.0: msdu-desc: 2500  skid: 32
Thu Nov 18 09:07:42 2021 kern.info kernel: [322184.044202] ath10k_pci 0000:00:00.0: wmi print 'P 48/48 V 16 K 144 PH 176 T 186  msdu-desc: 2500  sw-crypt: 0 ct-sta: 0'
Thu Nov 18 09:07:42 2021 kern.info kernel: [322184.055614] ath10k_pci 0000:00:00.0: wmi print 'free: 114572 iram: 12900 sram: 29508'
Thu Nov 18 09:07:42 2021 kern.info kernel: [322184.371007] ath10k_pci 0000:00:00.0: rts threshold -1
Thu Nov 18 09:07:42 2021 kern.warn kernel: [322184.376850] ath10k_pci 0000:00:00.0: Firmware lacks feature flag indicating a retry limit of > 2 is OK, requested limit: 4
Thu Nov 18 09:07:42 2021 kern.info kernel: [322184.393666] br-lan: port 2(wlan0) entered blocking state
Thu Nov 18 09:07:42 2021 kern.info kernel: [322184.399305] br-lan: port 2(wlan0) entered disabled state
Thu Nov 18 09:07:42 2021 kern.info kernel: [322184.405183] device wlan0 entered promiscuous mode
Thu Nov 18 09:07:42 2021 daemon.notice hostapd: wlan0: interface state UNINITIALIZED->COUNTRY_UPDATE
Thu Nov 18 09:07:42 2021 daemon.notice hostapd: wlan0: interface state COUNTRY_UPDATE->HT_SCAN
Thu Nov 18 09:07:42 2021 daemon.notice hostapd: wlan0: interface state HT_SCAN->DFS
Thu Nov 18 09:07:42 2021 daemon.notice hostapd: wlan0: DFS-CAC-START freq=5520 chan=104 sec_chan=-1, width=1, seg0=106, seg1=0, cac_time=60s
Thu Nov 18 09:08:44 2021 daemon.notice hostapd: wlan0: DFS-CAC-COMPLETED success=1 freq=5520 ht_enabled=0 chan_offset=0 chan_width=3 cf1=5530 cf2=0
Thu Nov 18 09:08:44 2021 kern.info kernel: [322246.207979] ath10k_pci 0000:00:00.0: mac flush null vif, drop 0 queues 0xffff
Thu Nov 18 09:08:44 2021 kern.info kernel: [322246.275208] IPv6: ADDRCONF(NETDEV_CHANGE): wlan0: link becomes ready
Thu Nov 18 09:08:44 2021 kern.info kernel: [322246.282072] br-lan: port 2(wlan0) entered blocking state
Thu Nov 18 09:08:44 2021 kern.info kernel: [322246.287691] br-lan: port 2(wlan0) entered forwarding state
Thu Nov 18 09:08:44 2021 daemon.notice netifd: Network device 'wlan0' link is up
Thu Nov 18 09:08:44 2021 daemon.notice hostapd: wlan0: interface state DFS->ENABLED
Thu Nov 18 09:08:44 2021 daemon.notice hostapd: wlan0: AP-ENABLED
Thu Nov 18 09:09:04 2021 daemon.info hostapd: wlan0: STA 8c:f5:a3:1c:75:03 IEEE 802.11: authenticated
Thu Nov 18 09:09:04 2021 daemon.notice hostapd: wlan0: STA-OPMODE-N_SS-CHANGED 8c:f5:a3:1c:75:03 1
Thu Nov 18 09:09:04 2021 daemon.info hostapd: wlan0: STA 8c:f5:a3:1c:75:03 IEEE 802.11: associated (aid 1)
Thu Nov 18 09:09:04 2021 daemon.notice hostapd: wlan0: AP-STA-CONNECTED 8c:f5:a3:1c:75:03
Thu Nov 18 09:09:04 2021 daemon.info hostapd: wlan0: STA 8c:f5:a3:1c:75:03 WPA: pairwise key handshake completed (RSN)
Thu Nov 18 09:11:01 2021 daemon.notice hostapd: wlan0: AP-STA-DISCONNECTED 8c:f5:a3:1c:75:03
Thu Nov 18 09:11:01 2021 daemon.notice hostapd: wlan0: STA-OPMODE-N_SS-CHANGED 8c:f5:a3:1c:75:03 1
Thu Nov 18 09:11:01 2021 daemon.info hostapd: wlan0: STA 8c:f5:a3:1c:75:03 IEEE 802.11: authenticated
Thu Nov 18 09:11:01 2021 daemon.info hostapd: wlan0: STA 8c:f5:a3:1c:75:03 IEEE 802.11: associated (aid 1)
Thu Nov 18 09:11:02 2021 daemon.notice hostapd: wlan0: AP-STA-CONNECTED 8c:f5:a3:1c:75:03
Thu Nov 18 09:11:02 2021 daemon.info hostapd: wlan0: STA 8c:f5:a3:1c:75:03 WPA: pairwise key handshake completed (RSN)
Thu Nov 18 09:11:03 2021 daemon.notice hostapd: wlan0: STA-OPMODE-N_SS-CHANGED 8c:f5:a3:1c:75:03 2

Thanks for any pointers.

Additional observation: the affected clients seem to be able to UPLOAD at ~100mb/s which is the limit of the fibre connection upload. It's download (to the clients) which suffers.

Is it all clients or only Samsung?

It's a Dell laptop running Linux Mint too. Also tested an iPhone and a Chromebook, they seem fine.

Is there a intel wifi chip on the laptop?

There was a tread here somewhere a short while ago that mentioned wifi problem with Intel wifi chip?

Hi flygarn12. Good call on the laptop chip, indeed it's an Intel Centrino Ultimate-N 6300. A search on these forums for "centrino" reveals possible issues with power management, so I switched off power management in linux and now it's pretty solid 90 Mb/s up and down from the laptop. Not as fast as I'd expect but at least faster than my old connection, and I mostly use the laptop wired anyhow.

The Samsung Galaxy S7 still drops to sub-20Mb/s speeds though.