From 8f34b648425e013c1aacf1d4b40ced99fab2f9fb96cd2e6a1cd785789554eb63 Mon Sep 17 00:00:00 2001 From: Ole Tange Date: Sat, 13 Jul 2024 15:01:25 +0200 Subject: [PATCH] slow-wifi: dmesg --- slow-wifi/README.txt | 59 ++++++++++++++++++++++++++++++++++++++++++++ slow-wifi/dmesg.txt | 13 ++++++++++ 2 files changed, 72 insertions(+) create mode 100644 slow-wifi/dmesg.txt diff --git a/slow-wifi/README.txt b/slow-wifi/README.txt index f8b2b9b..ce3b230 100644 --- a/slow-wifi/README.txt +++ b/slow-wifi/README.txt @@ -1,3 +1,58 @@ +I have an IBM T420 running Ubuntu 24.04. + +The wifi acts weird: Over time it slows to a crawl, but if I +disconnect and reconnect then the speed recovers to the expected +speed. + +This is not a fluke: You might expect the wifi or my internet +connection to be overloaded now and then, but this is reproducible. + +It sometime recover the speed by itself, but it is reproducible: Any +time it is slow, simply reconnect wifi and the speed recovers. + +I did this `timeout 10 tcpdump -ni all` before and after reconnecting +wifi. + +Note how the maximal time between packets is huge in the slow +situation (number in ms since last packet): + + $ grep -v lo tcpdump.slow.txt | + perl -pe 's/://g; s/^(\S+)/($1-$last)*1000/e;$last=$1;s/win.*//' | + sort -n | head -n -1 | tail + 138.347000000067 wlp3s0 Out IP 192.168.100.133.53472 > 192.168.100.1.53 16660+ [1au] A? www.youtube.com. (44) + 143.536000003223 wlp3s0 In IP 91.189.91.42.443 > 192.168.100.133.41830 Flags [.], seq 3920040600, ack 1, + 145.438999999897 wlp3s0 In IP 172.217.145.198.443 > 192.168.100.133.33518 Flags [.], seq 217117218513, ack 4, + 161.396000010427 wlp3s0 In IP 91.189.91.42.443 > 192.168.100.133.41830 Flags [.], seq 1400015400, ack 1, + 163.872000004631 wlp3s0 In IP 172.217.145.198.443 > 192.168.100.133.33518 Flags [.], seq 9287394269, ack 4, + 209.784000006039 wlp3s0 In IP 172.217.145.198.443 > 192.168.100.133.33518 Flags [P.], seq 4401345409, ack 4, + 230.691000004299 wlp3s0 In IP 91.189.91.42.443 > 192.168.100.133.41830 Flags [.], seq 42949602964294961696, ack 1, + 239.476000002469 wlp3s0 In IP 172.217.145.198.443 > 192.168.100.133.33518 Flags [.], seq 2028121677, ack 4, + 244.7780000075 wlp3s0 In IP 91.189.91.42.443 > 192.168.100.133.41830 Flags [.], seq 1540016800, ack 1, + 453.129999994417 wlp3s0 In IP 91.189.91.42.443 > 192.168.100.133.41830 Flags [.], seq 23102893132310290713, ack 3045969685, + +But small in the fast situation: + + $ grep -v lo tcpdump.fast.txt | + perl -pe 's/://g; s/^(\S+)/($1-$last)*1000/e;$last=$1;s/win.*//' | + sort -n | head -n -1 | tail + 14.2179999966174 wlp3s0 In IP 122.2.214.142.443 > 192.168.100.133.48242 Flags [F.], seq 205202, ack 1933, + 14.4089999957941 wlp3s0 In IP 91.189.91.42.443 > 192.168.100.133.41830 Flags [.], seq 7000071400, ack 1, + 15.348000000813 wlp3s0 In IP 91.189.91.42.443 > 192.168.100.133.41830 Flags [.], seq 922600924000, ack 1, + 15.8539999974892 wlp3s0 In IP 122.2.214.142.443 > 192.168.100.133.48218 Flags [.], ack 1931, + 18.1480000028387 wlp3s0 In IP 202.138.160.143.443 > 192.168.100.133.58298 Flags [.], seq 131932133332, ack 1936, + 19.9160000047414 wlp3s0 In IP 122.2.214.142.443 > 192.168.100.133.48262 Flags [.], seq 3640537805, ack 1932, + 24.6269999915967 wlp3s0 In IP 91.189.91.42.443 > 192.168.100.133.41830 Flags [.], seq 1960021000, ack 1, + 29.4679999933578 wlp3s0 In IP 202.138.160.143.443 > 192.168.100.133.56522 Flags [F.], seq 5944, ack 1936, + 33.2009999983711 wlp3s0 In IP 202.138.160.143.443 > 192.168.100.133.56522 Flags [.], ack 1936, + 120.297000001301 wlp3s0 In IP 202.138.160.143.443 > 192.168.100.133.56522 Flags [P.], seq 42014531, ack 518, + +What causes this? + +https://git.data.coop/tange/Test/src/branch/main/slow-wifi + +dmesg.txt +- dmesg entries when reconnecting wifi + iwconfig.txt - ifconfig -a @@ -11,9 +66,13 @@ uname: - uname -a tcpdump.slow.txt: +- Download big YouTube videos - Wait until wifi is slow - timeout 10 tcpdump -ni all +- 884 packets tcpdump.fast.txt: +- Continue downloading big YouTube videos - Disconnect and reconnect wifi (done immediately after slow) - timeout 10 tcpdump -ni all +- 32029 packets diff --git a/slow-wifi/dmesg.txt b/slow-wifi/dmesg.txt new file mode 100644 index 0000000..057a8be --- /dev/null +++ b/slow-wifi/dmesg.txt @@ -0,0 +1,13 @@ +Disconnect wifi: + +[133788.817139] wlp3s0: deauthenticating from 44:e9:68:6b:5a:4c by local choice (Reason: 3=DEAUTH_LEAVING) + +Reconnect wifi: + +[133797.689225] wlp3s0: authenticate with 44:e9:68:6b:5a:4c (local address=8c:a9:82:92:77:90) +[133797.689234] wlp3s0: send auth to 44:e9:68:6b:5a:4c (try 1/3) +[133797.794490] wlp3s0: send auth to 44:e9:68:6b:5a:4c (try 2/3) +[133797.799043] wlp3s0: authenticated +[133797.800483] wlp3s0: associate with 44:e9:68:6b:5a:4c (try 1/3) +[133797.804761] wlp3s0: RX AssocResp from 44:e9:68:6b:5a:4c (capab=0x1431 status=0 aid=85) +[133797.809892] wlp3s0: associated