WiFi slows to a crawl under heavy load - Intel AGN 5300

Jonhoo · 2011-02-01 13:14:10

Hey fellow archers!

I've recently installed Arch on my Dell E6400 which has a Intel AGN 5300 N Wireless card in it:

$ lshw -C Network
--[ cut ]--
*-network
       description: Wireless interface
       product: Ultimate N WiFi Link 5300
       vendor: Intel Corporation
       physical id: 0
       bus info: pci@0000:0c:00.0
       logical name: wlan0
       version: 00
       serial: 00:16:ea:60:93:5c
       width: 64 bits
       clock: 33MHz
       capabilities: pm msi pciexpress bus_master cap_list ethernet physical wireless
       configuration: broadcast=yes driver=iwlagn driverversion=2.6.37-ARCH firmware=8.24.2.12 ip=10.0.1.3 latency=0 link=yes multicast=yes wireless=IEEE 802.11abg
       resources: irq:43 memory:f1ffe000-f1ffffff

It works completely fine, even on WPA2/AES with N turned on. The problem occurs whenever I attempt to do anything where the speed approaches ~200kbps (copy file from a network share for instance), then it seems to really be struggling. This copy operation works fine on another laptop I have running Arch which reaches much higher speeds..
Occasionally, an error shows up in dmesg:

Feb  1 22:17:58 localhost kernel: iwlagn 0000:0c:00.0: low ack count detected, restart firmware
Feb  1 22:17:58 localhost kernel: iwlagn 0000:0c:00.0: On demand firmware reload
Feb  1 22:17:58 localhost kernel: iwlagn 0000:0c:00.0: Stopping AGG while state not ON or starting
Feb  1 22:17:58 localhost kernel: iwlagn 0000:0c:00.0: queue number out of range: 0, must be 10 to 19
Feb  1 22:18:09 localhost kernel: iwlagn 0000:0c:00.0: iwlagn_tx_agg_start on ra = 00:22:75:60:2b:3c tid = 0
Feb  1 22:18:57 localhost kernel: lo: Disabled Privacy Extensions
Feb  1 22:18:58 localhost kernel: chromium-sandbo (28377): /proc/28373/oom_adj is deprecated, please use /proc/28373/oom_score_adj instead.
Feb  1 22:22:58 localhost kernel: iwlagn 0000:0c:00.0: Microcode SW error detected.  Restarting 0x2000000.
Feb  1 22:22:58 localhost kernel: iwlagn 0000:0c:00.0: Loaded firmware version: 8.24.2.12
Feb  1 22:22:58 localhost kernel: iwlagn 0000:0c:00.0: Start IWL Error Log Dump:
Feb  1 22:22:58 localhost kernel: iwlagn 0000:0c:00.0: Status: 0x000212E4, count: 5
Feb  1 22:22:58 localhost kernel: iwlagn 0000:0c:00.0: Desc                                  Time       data1      data2      line
Feb  1 22:22:58 localhost kernel: iwlagn 0000:0c:00.0: NMI_INTERRUPT_WDG            (0x0004) 3255939758 0x00000002 0x07030000 3664
Feb  1 22:22:58 localhost kernel: iwlagn 0000:0c:00.0: pc      blink1  blink2  ilink1  ilink2  hcmd
Feb  1 22:22:58 localhost kernel: iwlagn 0000:0c:00.0: 0x006E4 0x005AA 0x006E8 0x008B2 0x0CF52 0xA7D001C
Feb  1 22:22:58 localhost kernel: iwlagn 0000:0c:00.0: CSR values:
Feb  1 22:22:58 localhost kernel: iwlagn 0000:0c:00.0: (2nd byte of CSR_INT_COALESCING is CSR_INT_PERIODIC_REG)
Feb  1 22:22:58 localhost kernel: iwlagn 0000:0c:00.0:        CSR_HW_IF_CONFIG_REG: 0X00480302
Feb  1 22:22:58 localhost kernel: iwlagn 0000:0c:00.0:          CSR_INT_COALESCING: 0X00000040
Feb  1 22:22:58 localhost kernel: iwlagn 0000:0c:00.0:                     CSR_INT: 0X00000000
Feb  1 22:22:58 localhost kernel: iwlagn 0000:0c:00.0:                CSR_INT_MASK: 0X00000000
Feb  1 22:22:58 localhost kernel: iwlagn 0000:0c:00.0:           CSR_FH_INT_STATUS: 0X00000000
Feb  1 22:22:58 localhost kernel: iwlagn 0000:0c:00.0:                 CSR_GPIO_IN: 0X00000000
Feb  1 22:22:58 localhost kernel: iwlagn 0000:0c:00.0:                   CSR_RESET: 0X00000000
Feb  1 22:22:58 localhost kernel: iwlagn 0000:0c:00.0:                CSR_GP_CNTRL: 0X080403c5
Feb  1 22:22:58 localhost kernel: iwlagn 0000:0c:00.0:                  CSR_HW_REV: 0X00000024
Feb  1 22:22:58 localhost kernel: iwlagn 0000:0c:00.0:              CSR_EEPROM_REG: 0X00000000
Feb  1 22:22:58 localhost kernel: iwlagn 0000:0c:00.0:               CSR_EEPROM_GP: 0X90000004
Feb  1 22:22:58 localhost kernel: iwlagn 0000:0c:00.0:              CSR_OTP_GP_REG: 0X00060000
Feb  1 22:22:58 localhost kernel: iwlagn 0000:0c:00.0:                 CSR_GIO_REG: 0X00080046
Feb  1 22:22:58 localhost kernel: iwlagn 0000:0c:00.0:            CSR_GP_UCODE_REG: 0X000013f2
Feb  1 22:22:58 localhost kernel: iwlagn 0000:0c:00.0:           CSR_GP_DRIVER_REG: 0X00000000
Feb  1 22:22:58 localhost kernel: iwlagn 0000:0c:00.0:           CSR_UCODE_DRV_GP1: 0X00000000
Feb  1 22:22:58 localhost kernel: iwlagn 0000:0c:00.0:           CSR_UCODE_DRV_GP2: 0X00000000
Feb  1 22:22:58 localhost kernel: iwlagn 0000:0c:00.0:                 CSR_LED_REG: 0X00000058
Feb  1 22:22:58 localhost kernel: iwlagn 0000:0c:00.0:        CSR_DRAM_INT_TBL_REG: 0X88115b46
Feb  1 22:22:58 localhost kernel: iwlagn 0000:0c:00.0:        CSR_GIO_CHICKEN_BITS: 0X27800200
Feb  1 22:22:58 localhost kernel: iwlagn 0000:0c:00.0:             CSR_ANA_PLL_CFG: 0X00880300
Feb  1 22:22:58 localhost kernel: iwlagn 0000:0c:00.0:           CSR_HW_REV_WA_REG: 0X0001001a
Feb  1 22:22:58 localhost kernel: iwlagn 0000:0c:00.0:        CSR_DBG_HPET_MEM_REG: 0Xffff0000
Feb  1 22:22:58 localhost kernel: iwlagn 0000:0c:00.0: FH register values:
Feb  1 22:22:58 localhost kernel: iwlagn 0000:0c:00.0:         FH_RSCSR_CHNL0_STTS_WPTR_REG: 0X118f1400
Feb  1 22:22:58 localhost kernel: iwlagn 0000:0c:00.0:        FH_RSCSR_CHNL0_RBDCB_BASE_REG: 0X011a4aa0
Feb  1 22:22:58 localhost kernel: iwlagn 0000:0c:00.0:                  FH_RSCSR_CHNL0_WPTR: 0X00000010
Feb  1 22:22:58 localhost kernel: iwlagn 0000:0c:00.0:         FH_MEM_RCSR_CHNL0_CONFIG_REG: 0X80819104
Feb  1 22:22:58 localhost kernel: iwlagn 0000:0c:00.0:          FH_MEM_RSSR_SHARED_CTRL_REG: 0X000000fc
Feb  1 22:22:58 localhost kernel: iwlagn 0000:0c:00.0:            FH_MEM_RSSR_RX_STATUS_REG: 0X07030000
Feb  1 22:22:58 localhost kernel: iwlagn 0000:0c:00.0:    FH_MEM_RSSR_RX_ENABLE_ERR_IRQ2DRV: 0X00000000
Feb  1 22:22:58 localhost kernel: iwlagn 0000:0c:00.0:                FH_TSSR_TX_STATUS_REG: 0X07ff0001
Feb  1 22:22:58 localhost kernel: iwlagn 0000:0c:00.0:                 FH_TSSR_TX_ERROR_REG: 0X00000000
Feb  1 22:22:58 localhost kernel: iwlagn 0000:0c:00.0: Start IWL Event Log Dump: display last 20 entries
Feb  1 22:22:58 localhost kernel: iwlagn 0000:0c:00.0: EVT_LOGT:0299295213:0x00000000:0302
Feb  1 22:22:58 localhost kernel: iwlagn 0000:0c:00.0: EVT_LOGT:0299295344:0x00000000:0304
Feb  1 22:22:58 localhost kernel: iwlagn 0000:0c:00.0: EVT_LOGT:0299295607:0x0000010f:0106
Feb  1 22:22:58 localhost kernel: iwlagn 0000:0c:00.0: EVT_LOGT:0299295609:0x00000000:0302
Feb  1 22:22:58 localhost kernel: iwlagn 0000:0c:00.0: EVT_LOGT:0299295740:0x00000000:0304
Feb  1 22:22:58 localhost kernel: iwlagn 0000:0c:00.0: EVT_LOGT:0299295757:0x0000010f:0106
Feb  1 22:22:58 localhost kernel: iwlagn 0000:0c:00.0: EVT_LOGT:0299295759:0x00000000:0302
Feb  1 22:22:58 localhost kernel: iwlagn 0000:0c:00.0: EVT_LOGT:0299295790:0x000000d4:0303
Feb  1 22:22:58 localhost kernel: iwlagn 0000:0c:00.0: EVT_LOGT:0299296122:0x0000010f:0106
Feb  1 22:22:58 localhost kernel: iwlagn 0000:0c:00.0: EVT_LOGT:0299296123:0x00000000:0302
Feb  1 22:22:58 localhost kernel: iwlagn 0000:0c:00.0: EVT_LOGT:0299296153:0x000000b4:0303
Feb  1 22:22:58 localhost kernel: iwlagn 0000:0c:00.0: EVT_LOGT:0299296162:0x000000c4:0322
Feb  1 22:22:58 localhost kernel: iwlagn 0000:0c:00.0: EVT_LOGT:0299296211:0x00000000:0302
Feb  1 22:22:58 localhost kernel: iwlagn 0000:0c:00.0: EVT_LOGT:0299296239:0x00000436:0323
Feb  1 22:22:58 localhost kernel: iwlagn 0000:0c:00.0: EVT_LOGT:0299296261:0x00000000:1350
Feb  1 22:22:58 localhost kernel: iwlagn 0000:0c:00.0: EVT_LOGT:0299296261:0x00000000:1351
Feb  1 22:22:58 localhost kernel: iwlagn 0000:0c:00.0: EVT_LOGT:0299296262:0x00000001:1352
Feb  1 22:22:58 localhost kernel: iwlagn 0000:0c:00.0: EVT_LOGT:0299296262:0x00000002:1353
Feb  1 22:22:58 localhost kernel: iwlagn 0000:0c:00.0: EVT_LOGT:0299496113:0x000000d7:0123
Feb  1 22:22:58 localhost kernel: iwlagn 0000:0c:00.0: EVT_LOGT:0299496121:0x00000000:0125
Feb  1 22:22:58 localhost kernel: iwlagn 0000:0c:00.0: Stopping AGG while state not ON or starting
Feb  1 22:22:58 localhost kernel: iwlagn 0000:0c:00.0: queue number out of range: 0, must be 10 to 19
Feb  1 22:23:00 localhost kernel: iwlagn 0000:0c:00.0: iwlagn_tx_agg_start on ra = 00:22:75:60:2b:3c tid = 0

Normally though, the only "error" that shows up is:

Feb  1 23:06:40 localhost kernel: iwlagn 0000:0c:00.0: Aggregation not enabled for tid 0 because load = 0
Feb  1 23:06:47 localhost kernel: iwlagn 0000:0c:00.0: Aggregation not enabled for tid 0 because load = 7
Feb  1 23:06:53 localhost kernel: iwlagn 0000:0c:00.0: iwlagn_tx_agg_start on ra = 00:22:75:60:2b:3c tid = 0

I've tried setting "option iwlagn swcrypto=1 11n_disable=1" in /etc/modprobe.d/wireless.conf", and that gets rid of the aggregation messages and allows me to reach speeds up to ~300kbps, but the speed still varies wildly although I am sitting three meters from the AP, and does not even allow streaming AVI video from a box sitting on the same network (wired)...

Also, I am getting strange results when pinging any given host..

PING 10.0.1.4 (10.0.1.4) 56(84) bytes of data.
64 bytes from 10.0.1.4: icmp_req=1 ttl=64 time=79.5 ms
64 bytes from 10.0.1.4: icmp_req=2 ttl=64 time=15.1 ms
64 bytes from 10.0.1.4: icmp_req=3 ttl=64 time=21.6 ms
64 bytes from 10.0.1.4: icmp_req=4 ttl=64 time=42.4 ms
64 bytes from 10.0.1.4: icmp_req=5 ttl=64 time=59.0 ms
64 bytes from 10.0.1.4: icmp_req=6 ttl=64 time=7.94 ms
64 bytes from 10.0.1.4: icmp_req=7 ttl=64 time=11.8 ms
64 bytes from 10.0.1.4: icmp_req=8 ttl=64 time=25.2 ms
64 bytes from 10.0.1.4: icmp_req=9 ttl=64 time=47.6 ms
64 bytes from 10.0.1.4: icmp_req=10 ttl=64 time=6.93 ms
64 bytes from 10.0.1.4: icmp_req=11 ttl=64 time=9.65 ms
64 bytes from 10.0.1.4: icmp_req=12 ttl=64 time=21.5 ms
64 bytes from 10.0.1.4: icmp_req=13 ttl=64 time=38.0 ms
64 bytes from 10.0.1.4: icmp_req=14 ttl=64 time=63.4 ms
^C
--- 10.0.1.4 ping statistics ---
14 packets transmitted, 14 received, 0% packet loss, time 13019ms
rtt min/avg/max/mdev = 6.935/32.160/79.567/22.412 ms

Notice how the latency keeps rising, then suddenly drops, and then rises again.. The same happens when pinging external IPs..

One last thing: I've noticed that a couple of times when the network speed starts to slow down, the "Invalid misc" counter in "iwconfig wlan0" rises quickly.. Don't know if this is relevant?

I'm wondering if this can be related to this bug: https://bugs.launchpad.net/linux/+bug/200509

Hope someone can shed some light on this..
Cheers,
Jon

mouse256 · 2011-02-02 13:28:12

Hi,

I have the same card (intel 5300 on dell studio 1555)
I'm also having issues, but not as bad as you. From time to time I suffer a quite huge packet loss, and then enabling/disabling wifi solves it again.

I have 11n still enabled, but my speed is not what it should be. (wpa2, 11n)
File copy in linux: 2mbyte/s
File copy in windows: 8mbyte/s

My problems seems like what is described here, and intel seems to have an experimental firmware, but I haven't tried that yet:
https://bugzilla.kernel.org/show_bug.cgi?id=16691#c82

Last edited by mouse256 (2011-02-02 13:28:52)

Arch Linux

#1 2011-02-01 13:14:10

WiFi slows to a crawl under heavy load - Intel AGN 5300

#2 2011-02-02 13:28:12

Re: WiFi slows to a crawl under heavy load - Intel AGN 5300

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