Bug 506659
| Summary: | ath5k: phy0 periodicaly uses considerable cpu and ssh connections lock up for several seconds | ||
|---|---|---|---|
| Product: | [Fedora] Fedora | Reporter: | Bidwell Ducanh <bidwell.ducanh> |
| Component: | kernel | Assignee: | John W. Linville <linville> |
| Status: | CLOSED UPSTREAM | QA Contact: | Fedora Extras Quality Assurance <extras-qa> |
| Severity: | low | Docs Contact: | |
| Priority: | low | ||
| Version: | 11 | CC: | eloranta, itamar, kernel-maint, quintela |
| Target Milestone: | --- | ||
| Target Release: | --- | ||
| Hardware: | i686 | ||
| OS: | Linux | ||
| Whiteboard: | |||
| Fixed In Version: | Doc Type: | Bug Fix | |
| Doc Text: | Story Points: | --- | |
| Clone Of: | Environment: | ||
| Last Closed: | 2009-06-30 13:59:54 UTC | Type: | --- |
| Regression: | --- | Mount Type: | --- |
| Documentation: | --- | CRM: | |
| Verified Versions: | Category: | --- | |
| oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |
| Cloudforms Team: | --- | Target Upstream Version: | |
| Embargoed: | |||
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Description
Bidwell Ducanh
2009-06-18 08:10:07 UTC
I realize this is probably related to ath5k's known rate-setting issues and the new minstrel rate algorithm. Please let me know if this is a duplicate or how I can contribute some more information. Actually, it sounds more like periodic scanning to me. Are you using NetworkManager? Yes, I'm using NetworkManager. I guess I should fall back to wpa_supplicant? That might be worthwhile, although honestly I'm not sure if NM is triggering scans or if wpa_supplicant does it. I wonder if you can recreate the issue with and open or WEP network? Also, it is probably worthwhile to run iwevent and see if there are any events coincident with the delays. I've confirmed by watching iwevent and iwconfig wlan0 that you were indeed correct that the periodic scanning is the culprit. On a WPA or open network iwevent will output: 11:41:56.761202 wlan0 Scan request completed periodically as iwconfig reports frequency change. This will coincide with the connection stalls and phy0 CPU usage. Furthermore, using wpa_supplicant and disabling NetworkManager, this behavior is not reproducible (perhaps only by manually triggering a scan?) OK, at least we understand the issue. FWIW, there has been some work done in the upstream kernel that will mitigate this issue. However, it will take some time for this to appear in Fedora -- could be F-12... Any progress on this? I am at FC12 and this problem still persists. I have: 2.6.31.5-127.fc12.i686.PAE When I ping my base station, I see occasionally: 64 bytes from 192.168.1.1: icmp_seq=57 ttl=64 time=1.33 ms 64 bytes from 192.168.1.1: icmp_seq=58 ttl=64 time=1.39 ms 64 bytes from 192.168.1.1: icmp_seq=59 ttl=64 time=1.39 ms 64 bytes from 192.168.1.1: icmp_seq=60 ttl=64 time=1.29 ms 64 bytes from 192.168.1.1: icmp_seq=61 ttl=64 time=4236 ms 64 bytes from 192.168.1.1: icmp_seq=62 ttl=64 time=3243 ms 64 bytes from 192.168.1.1: icmp_seq=63 ttl=64 time=2244 ms 64 bytes from 192.168.1.1: icmp_seq=64 ttl=64 time=1244 ms 64 bytes from 192.168.1.1: icmp_seq=65 ttl=64 time=237 ms 64 bytes from 192.168.1.1: icmp_seq=66 ttl=64 time=1.34 ms 64 bytes from 192.168.1.1: icmp_seq=67 ttl=64 time=1.24 ms 64 bytes from 192.168.1.1: icmp_seq=68 ttl=64 time=1.28 ms 64 bytes from 192.168.1.1: icmp_seq=69 ttl=64 time=1.83 ms The system is doing scan at the points when this happens. I am using NetworkManager. This is a really annoying problem as it makes the system very difficult to use (especially ssh connections stop from time to time and make editing files pain). (the system where I see this is an up to date FC12 as of Nov-28 2009) lspci says: 03:00.0 Ethernet controller: Atheros Communications Inc. AR242x 802.11abg Wireless PCI Express Adapter (rev 01) |