Re: 2.6.20-rc1: CIFS cheers, NFS4 jeers

Andrew Morton
2007-03-01T05:52:54Z

On Mon, 26 Feb 2007 00:45:00 -0600 florin@iucha.net (Florin Iucha) wrote:

> Hello, it's me and my 70 GB of photos again.
>
> I have tested both CIFS and NFSv4 clients in kernel 2.6.20-rc1 . CIFS
> passed with flying colors and NFSv4 stalled after 7 GB.
>
> Configuration:
>
> Server: PIII/1GHz, 512 MB RAM, Debian testing,
> distro kernel 2.6.18-3-vserver-686, Intel E1000 NIC,
> filesystem 170 GB ext3 with default mkfs values on a SATA disk
>
> Client: AMD x2 4200+, 2 GB RAM, Debian testing/unstable
> kernel 2.6.20-rc1, Marvell SKGE onboard,
> filesystem 120 GB ext3 with default mkfs values on a SATA disk
>
> After the writing stalls, I have echoed 't' into /proc/sysrq-trigger
> and got a trace, which is at http://iucha.net/20-rc1/after.1. There was
> no oops before the trace request; the 'before' dmesg is at
> http://iucha.net/20-rc1/before.1 .
>
> Running 'top', one core is idle and the other is 99% waiting, while
> the 'cp' program is in 'D' state. Also, after NFSv4 stalls, invokations
> of 'lsof' stall as well. I can 'ssh' into the box without problems.

and

>
> The kernel on the client is 2.6.21-rc1 (but it echoes problems I
> reported in December with 2.6.20 series as well) as can be seen from
> the kernel logs.
>
> I have corrected the links:
>
> http://iucha.net/21-rc1/before.1
> http://iucha.net/21-rc1/after.1
> http://iucha.net/21-rc1/config-2.6.21-rc1
>

The relevant part is:

[ 1215.657827] cp D 000000f86f105704 0 2859 2843 (NOTLB)
[ 1215.657833] ffff81007343faa8 0000000000000082 0000000000000000 ffff81007343fb58
[ 1215.657837] 0000000000000002 ffff81007343faa8 0000000000000008 ffff81007e578ee0
[ 1215.657842] ffff810002f4a080 0000000000002150 ffff81007e5790b8 000000017343fb50
[ 1215.657847] Call Trace:
[ 1215.657852] [<ffffffff80160f4c>] io_schedule+0x28/0x34
[ 1215.657856] [<ffffffff80128517>] sync_page+0x41/0x45
[ 1215.657859] [<ffffffff80161294>] __wait_on_bit+0x45/0x77
[ 1215.657862] [<ffffffff801284d6>] sync_page+0x0/0x45
[ 1215.657867] [<ffffffff8013370c>] wait_on_page_bit+0x6e/0x75
[ 1215.657870] [<ffffffff801948ca>] wake_bit_function+0x0/0x2a
[ 1215.657874] [<ffffffff801454a2>] pagevec_lookup_tag+0x22/0x2b
[ 1215.657878] [<ffffffff80147317>] wait_on_page_writeback_range+0x6e/0x142
[ 1215.657885] [<ffffffff801a4a79>] filemap_fdatawait+0x20/0x22
[ 1215.657889] [<ffffffff801a4bfe>] filemap_write_and_wait+0x29/0x38
[ 1215.657894] [<ffffffff8023019a>] nfs_setattr+0xa0/0x11a
[ 1215.657897] [<ffffffff8010e30e>] link_path_walk+0xe8/0xfc
[ 1215.657902] [<ffffffff80194892>] autoremove_wake_function+0x0/0x38
[ 1215.657907] [<ffffffff80112377>] poison_obj+0x27/0x32
[ 1215.657910] [<ffffffff8010db3a>] current_fs_time+0x3f/0x41
[ 1215.657913] [<ffffffff80122f93>] __user_walk_fd+0x53/0x62
[ 1215.657918] [<ffffffff8012bc1b>] notify_change+0x129/0x238
[ 1215.657923] [<ffffffff801c5ccb>] do_utimes+0xfc/0x126
[ 1215.657928] [<ffffffff801077fc>] _raw_spin_lock+0xf3/0xf9
[ 1215.657933] [<ffffffff801c5d3a>] sys_futimesat+0x45/0x56
[ 1215.657937] [<ffffffff80150d3e>] sys_utimes+0x14/0x16
[ 1215.657941] [<ffffffff8015ac5e>] system_call+0x7e/0x83

seems that we've simply lost an IO completion.

Was 2.6.19 OK?