[Crash-utility] [PATCH] fix vmstat handling

[Dave Anderson]

----- Original Message -----
> On Thu, Nov 2, 2017 at 8:58 PM, Dave Anderson <anderson at redhat.com> wrote:
> >
> >
> > ----- Original Message -----
> >> From: Vinayak Menon <vinayakm.list at gmail.com>
> >>
> >> With kernels where LRUs are moved to node and thus vm_stat is
> >> split into zone and node, crash utility fails to show the vmstat with
> >> "kmem
> >> -V", and the "CACHED" of kmem -i is shown as zero.
> >>
> >> Signed-off-by: Vinayak Menon <vinayakm.list at gmail.com>
> >
> > Nice -- thanks for catching this!
> >
> > But can you re-send the patch as an attachment?  It appears that the
> > inlined patch below has all tabs replaced with spaces:
> >
> Sure. Attached.

Hi Vinayak,

I understand that this kernel change was introduced in 4.8, and
I don't have a lot of 4.8 and later kernels to test with. 

But of the ones I do have, the 4.8, 4.13 and 4.14 kernels tested OK,
but both of my 4.11.0-based kernels show the same type of bogus
CACHED values:

  crash> kmem -i
                   PAGES        TOTAL      PERCENTAGE
      TOTAL MEM   970244       3.7 GB         ----
           FREE   225486     880.8 MB   23% of TOTAL MEM
           USED   744758       2.8 GB   76% of TOTAL MEM
         SHARED   290313       1.1 GB   29% of TOTAL MEM
        BUFFERS      554       2.2 MB    0% of TOTAL MEM
         CACHED  40129611715  153082.3 GB  4136032% of TOTAL MEM
           SLAB    49489     193.3 MB    5% of TOTAL MEM
  
     TOTAL HUGE        0            0         ----
      HUGE FREE        0            0    0% of TOTAL HUGE
  
     TOTAL SWAP  1015807       3.9 GB         ----
      SWAP USED        0            0    0% of TOTAL SWAP
      SWAP FREE  1015807       3.9 GB  100% of TOTAL SWAP
  
   COMMIT LIMIT  1500929       5.7 GB         ----
      COMMITTED   104016     406.3 MB    6% of TOTAL LIMIT
  crash> 

and:
  
  crash> kmem -i
                   PAGES        TOTAL      PERCENTAGE
      TOTAL MEM  16439775      62.7 GB         ----
           FREE  15456286        59 GB   94% of TOTAL MEM
           USED   983489       3.8 GB    5% of TOTAL MEM
         SHARED   607536       2.3 GB    3% of TOTAL MEM
        BUFFERS     1043       4.1 MB    0% of TOTAL MEM
         CACHED  44353900800  169196.7 GB  269796% of TOTAL MEM
           SLAB    75430     294.6 MB    0% of TOTAL MEM
  
     TOTAL HUGE        0            0         ----
      HUGE FREE        0            0    0% of TOTAL HUGE
  
     TOTAL SWAP  3568639      13.6 GB         ----
      SWAP USED        0            0    0% of TOTAL SWAP
      SWAP FREE  3568639      13.6 GB  100% of TOTAL SWAP
  
   COMMIT LIMIT  11788526        45 GB         ----
      COMMITTED    89997     351.6 MB    0% of TOTAL LIMIT
   crash> 

Can you take a look at what happened in those dumpfiles?  I'm
guessing there's some negative number involved somewhere.
  
I'll send a link to their download location in a private email.

Thanks,
  Dave