Re: Huge memory takes too long time to initialize on 4TB ?

[Andrea Arcangeli <aarcange@redhat.com>]

On Wed, May 23, 2012 at 09:48:17PM -0700, David Rientjes wrote:
> On Thu, 24 May 2012, ethan zhao wrote:
> 
> > BUG: soft lockup - CPU#60 stuck for 21s! [swapper:1]
> > Modules linked in:
> > CPU 60
> > Modules linked in:
> > 
> > Pid: 1, comm: swapper Not tainted 2.6.39-100.6.1.el6uek.x86_64 #1
> > Oracle Corporation  Sun Fire X4800 M2 /
> > RIP: 0010:[<ffffffff814fb2d9>]  [<ffffffff814fb2d9>]
> > _raw_spin_unlock_irqrestore+0x19/0x30
> > RSP: 0000:ffff887d8efbfe38  EFLAGS: 00000286
> > RAX: 0000000038080200 RBX: ffff887d8efbfe00 RCX: 0340000000000400
> > RDX: ffffea0c41bfe8d0 RSI: 0000000000000286 RDI: 0000000000000286
> > RBP: ffff887d8efbfe40 R08: 0000000000000004 R09: 0000000000000000
> > R10: ffff8b807ffcbfe8 R11: 0000000000014f50 R12: ffffffff81503f4e
> > R13: ffffea0a81c00000 R14: ffff897d8d69b060 R15: ffff897d8d69b000
> > FS:  0000000000000000(0000) GS:ffff8b807f800000(0000) knlGS:0000000000000000
> > CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> > CR2: 0000000000000000 CR3: 0000000001761000 CR4: 00000000000006e0
> > DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
> > DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
> > Process swapper (pid: 1, threadinfo ffff887d8efbe000, task ffff887d8efbc040)
> > Stack:
> >  ffff8b807ffece00 ffff887d8efbfe80 ffffffff811105d1 ffff887d8efbfe80
> >  ffffffff819aee60 0000000000000000 ffffffff814f7483 0000000000000000
> >  0000000000000000 ffff887d8efbfea0 ffffffff814f74c0 ffffffff819aee58
> > Call Trace:
> >  [<ffffffff811105d1>] setup_per_zone_wmarks+0xb1/0xe0
> >  [<ffffffff814f7483>] ? free_area_init_node+0xcb/0xcb
> >  [<ffffffff814f74c0>] init_per_zone_wmark_min+0x3d/0x8b
> >  [<ffffffff81002043>] do_one_initcall+0x43/0x190
> >  [<ffffffff818c46fd>] kernel_init+0x15b/0x1e6
> >  [<ffffffff815046a4>] kernel_thread_helper+0x4/0x10
> >  [<ffffffff818c45a2>] ? parse_early_options+0x20/0x20
> >  [<ffffffff815046a0>] ? gs_change+0x13/0x13
> 
> Yeah, this confirms what I was suspecting in that its a soft lockup 
> because irqs aren't getting enabled for a lengthy period of time due to 

Yep, reading the prefix clarified things.

> how long setup_per_zone_wmarks() takes for your system with 4TB of RAM.  
> 3.3 or later kernels should significantly improve this.  If there's still 
> an issue, please let us know.

Agreed!

Anyway these should be just warnings, if BOOTPARAM_SOFTLOCKUP_PANIC
isn't set (and it looks like it's not) it won't harm. So it's not
concerning at all, and you can safely ignore all these warnings as
long as they happen only at boot time.

Thanks,
Andrea