Lock contention in AIO

[Slawa Olhovchenkov]

I am see lock contetntion cuased by aio read (same file segment from
multiple process simultaneous):

07.74%  [26756]    lock_delay @ /boot/kernel/kernel
 92.21%  [24671]     __mtx_lock_sleep
  52.14%  [12864]      vm_page_enqueue
   100.0%  [12864]       vm_fault_hold
    87.71%  [11283]        vm_fault_quick_hold_pages
     100.0%  [11283]         vn_io_fault1
      100.0%  [11283]          vn_io_fault
       99.88%  [11270]           aio_process_rw
        100.0%  [11270]            aio_daemon
         100.0%  [11270]             fork_exit
       00.12%  [13]              dofileread
        100.0%  [13]               kern_readv

Is this know problem?