Re: strange guest slowness after some time

[Tomasz Chmielewski <mangoo@wpkg.org>]

Tomasz Chmielewski schrieb:

> Sorry, both machines run Debian Lenny and 2.6.26 kernel.
> The only difference is that machine which crashes (with MTU=100) or 
> locks up (with MTU=1500) runs a "2.6.26-1-686" kernel and the one which 
> doesn't lock up runs "2.6.26-1-486" kernel (both are Debian's kernels).

Some more tries and I got this one. Serial console died, but SSH is still working.

Note the "S" tainted flag.
According to Documentation/oops-tracing.txt, it means:

  3: 'S' if the oops occurred on an SMP kernel running on hardware that
     hasn't been certified as safe to run multiprocessor.
     Currently this occurs only on various Athlons that are not
     SMP capable.


And this is a difference between "2.6.26-1-686" and "2.6.26-1-486" kernels.

# grep -i smp /boot/config-2.6.26-1-686
CONFIG_X86_SMP=y
CONFIG_X86_32_SMP=y
CONFIG_SMP=y


# grep -i smp /boot/config-2.6.26-1-486
CONFIG_BROKEN_ON_SMP=y
# CONFIG_SMP is not set



[10942.216450] BUG: soft lockup - CPU#0 stuck for 760s! [postgres:1802]
[10942.216450] Modules linked in: ipv6 loop joydev virtio_balloon virtio_net parport_pc parport snd_pcsp serio_raw snd_pcm snd_timer psmouse snd soundcore snd_page_alloc i2c_piix4 i2c_core button usbhid hid ff_memless evdev ext3 jbd mbcache virtio_blk ide_cd_mod cdrom ide_pci_generic floppy virtio_pci uhci_hcd usbcore piix ide_core ata_generic libata scsi_mod dock thermal processor fan thermal_sys
[10942.216450]
[10942.216450] Pid: 1802, comm: postgres Tainted: G S        (2.6.26-1-686 #1)
[10942.216450] EIP: 0060:[<c011d5a0>] EFLAGS: 00000206 CPU: 0
[10942.216450] EIP is at finish_task_switch+0x25/0x99
[10942.216450] EAX: c1208fa0 EBX: c03bafa0 ECX: c1208fa0 EDX: ce0be4a0
[10942.216450] ESI: 00000000 EDI: ce0be4a0 EBP: 00000001 ESP: ce7f9afc
[10942.216450]  DS: 007b ES: 007b FS: 00d8 GS: 0033 SS: 0068
[10942.216450] CR0: 8005003b CR2: 080f3a10 CR3: 0eaeb000 CR4: 000006d0
[10942.216450] DR0: 00000000 DR1: 00000000 DR2: 00000000 DR3: 00000000
[10942.216450] DR6: ffff0ff0 DR7: 00000400
[10942.216450]  [<c02b82ee>] ? schedule+0x60c/0x66f
[10942.216450]  [<c0129ab0>] ? lock_timer_base+0x19/0x35
[10942.216450]  [<c0129bc3>] ? __mod_timer+0x99/0xa3
[10942.216450]  [<c02b8549>] ? schedule_timeout+0x6b/0x86
[10942.216450]  [<c01297ec>] ? process_timeout+0x0/0x5
[10942.216450]  [<c02b8544>] ? schedule_timeout+0x66/0x86
[10942.216450]  [<c017f2c6>] ? do_select+0x364/0x3bd
[10942.216450]  [<c017f7ca>] ? __pollwait+0x0/0xac
[10942.216450]  [<d08e74c4>] ? start_xmit+0x9f/0xa5 [virtio_net]
[10942.216450]  [<c025895c>] ? dev_hard_start_xmit+0x1eb/0x24f
[10942.216450]  [<c02669f2>] ? __qdisc_run+0xcc/0x17c
[10942.216450]  [<c025abbf>] ? dev_queue_xmit+0x287/0x2bc
[10942.216450]  [<c02762cd>] ? ip_finish_output+0x1c5/0x1fc
[10942.216450]  [<c0115403>] ? pvclock_clocksource_read+0x4b/0xd0
[10942.216450]  [<c0275e5b>] ? ip_local_out+0x15/0x17
[10942.216450]  [<c013604c>] ? getnstimeofday+0x37/0xbc
[10942.216450]  [<c01344c2>] ? ktime_get_ts+0x22/0x49
[10942.216450]  [<c01344f6>] ? ktime_get+0xd/0x21
[10942.216450]  [<c01190e6>] ? hrtick_start_fair+0xeb/0x12c
[10942.216450]  [<c011b39f>] ? task_rq_lock+0x3b/0x5e
[10942.216450]  [<c02531ab>] ? skb_checksum+0x52/0x272
[10942.216450]  [<c017f5a1>] ? core_sys_select+0x282/0x29f
[10942.216450]  [<c0129ccb>] ? mod_timer+0x19/0x36
[10942.216450]  [<c0252345>] ? sock_def_readable+0xf/0x58
[10942.216450]  [<c0283cf4>] ? tcp_rcv_established+0x51d/0x7b1
[10942.216450]  [<c0288d9f>] ? tcp_v4_do_rcv+0x262/0x3e8
[10942.216450]  [<c028ab5d>] ? tcp_v4_rcv+0x5b6/0x609
[10942.216450]  [<c0272ec3>] ? ip_local_deliver_finish+0xe8/0x183
[10942.216450]  [<c0272dbe>] ? ip_rcv_finish+0x286/0x2a3
[10942.216450]  [<c025837a>] ? netif_receive_skb+0x2d6/0x343
[10942.216450]  [<d08e7aa9>] ? virtnet_poll+0x21d/0x258 [virtio_net]
[10942.216450]  [<c017f915>] ? sys_select+0x9f/0x180
[10942.216450]  [<c0103853>] ? sysenter_past_esp+0x78/0xb1
[10942.216450]  =======================



-- 
Tomasz Chmielewski
http://wpkg.org