Ubuntu + NFS + PHP - file lock. Why ?

Question

PHP

There are 2 servers on Ubuntu.
On the first NFS server is up.
cat /etc/exports

/home/XXXX/www XX.XX.XX.XX(rw,async,insecure,nohide,all_squash,anonuid=1000,anongid=1000,no_subtree_check)

On the second one, it is connected via mount
mount XX.XX.XX.XX:/home/XXX/www /home/XXX/www
FS seems to be ok. But I start PHP "hangs" on blocking FS
#echo w > /proc/sysrq-trigger; dmesg -c | less

[5950692.476837] SysRq : Show Blocked State
[5950692.477069]   task                        PC stack   pid father
[5950692.477097] php             D ffffffff81806240     0  8648   7742 0x00000000
[5950692.477102]  ffff8805f49e9a88 0000000000000086 ffff88041b44eed0 0000000000000020
[5950692.477106]  ffff8805f49e9fd8 ffff8805f49e9fd8 ffff8805f49e9fd8 00000000000137c0
[5950692.477110]  ffffffff81c0d020 ffff8805f3125c00 0000000000000282 ffff8805f49e9b10
[5950692.477114] Call Trace:
[5950692.477131]  [<ffffffffa045de30>] ? rpc_complete_task+0xa0/0xa0 [sunrpc]
[5950692.477136]  [<ffffffff816617ef>] schedule+0x3f/0x60
[5950692.477145]  [<ffffffffa045de54>] rpc_wait_bit_killable+0x24/0x40 [sunrpc]
[5950692.477148]  [<ffffffff816620af>] __wait_on_bit+0x5f/0x90
[5950692.477156]  [<ffffffffa045de30>] ? rpc_complete_task+0xa0/0xa0 [sunrpc]
[5950692.477159]  [<ffffffff8166215c>] out_of_line_wait_on_bit+0x7c/0x90
[5950692.477164]  [<ffffffff8108c3b0>] ? autoremove_wake_function+0x40/0x40
[5950692.477172]  [<ffffffffa045ec45>] __rpc_execute+0xf5/0x1d0 [sunrpc]
[5950692.477181]  [<ffffffffa045ef43>] rpc_execute+0x43/0x50 [sunrpc]
[5950692.477187]  [<ffffffffa0456a55>] rpc_run_task+0x75/0x90 [sunrpc]
[5950692.477194]  [<ffffffffa0456b73>] rpc_call_sync+0x43/0x70 [sunrpc]
[5950692.477200]  [<ffffffffa04adb63>] nlmclnt_call+0xa3/0x250 [lockd]
[5950692.477204]  [<ffffffffa04ae6fe>] nlmclnt_lock+0xce/0x280 [lockd]
[5950692.477208]  [<ffffffffa04aeaba>] nlmclnt_proc+0x10a/0x1e0 [lockd]
[5950692.477225]  [<ffffffffa04e0295>] nfs3_proc_lock+0x25/0x30 [nfs]
[5950692.477233]  [<ffffffffa04cc6dd>] do_setlk+0xed/0x110 [nfs]
[5950692.477241]  [<ffffffffa04cc899>] nfs_lock+0xb9/0x1b0 [nfs]
[5950692.477245]  [<ffffffff811c6d73>] vfs_lock_file+0x23/0x40
[5950692.477248]  [<ffffffff811c6e94>] do_lock_file_wait+0x54/0x100
[5950692.477251]  [<ffffffff811c598f>] ? locks_alloc_lock+0x1f/0x60
[5950692.477254]  [<ffffffff811c7965>] fcntl_setlk+0x115/0x220
[5950692.477258]  [<ffffffff8118c412>] do_fcntl+0x1b2/0x350
[5950692.477261]  [<ffffffff8118c61b>] sys_fcntl+0x6b/0xa0
[5950692.477265]  [<ffffffff8166bd42>] system_call_fastpath+0x16/0x1b
[5950692.477270] Sched Debug Version: v0.10, 3.2.0-67-generic #101-Ubuntu
[5950692.477273] ktime                                   : 5953234698.849797
[5950692.477275] sched_clk                               : 5950692477.269732
[5950692.477276] cpu_clk                                 : 5950692477.269802
[5950692.477278] jiffies                                 : 5783200970
[5950692.477280] sched_clock_stable                      : 1

What am I doing wrong ?

Answer 1

Well, show the script on which everything hangs for you?
Servers in one