[Bug testsuite/23493] Test suite makes all CPU stuck forever on kernel 4.16.16 (Fedora 27)

["agentzh at gmail dot com" <sourceware-bugzilla@sourceware.org>]

https://sourceware.org/bugzilla/show_bug.cgi?id=23493

--- Comment #7 from agentzh <agentzh at gmail dot com> ---
It seems like that the stuck usually happens after running
`uprobes_onthefly.exp` and/or `kprobes_onthefly.exp`. By checking the
`/proc/buddyinfo` output during the nearby time window, the fragmentation
becomes dramatically worse, for example:

```
$ cat /proc/buddyinfo
Node 0, zone      DMA      0      0      0      0      2      1      1      0  
   1      1      3
Node 0, zone    DMA32     14     23     27     27     23     12     17     16  
   9      4    739
Node 0, zone   Normal    379   4113   3506   3803   2461    733    221      0  
   0      0      0

$ cat /proc/buddyinfo
Node 0, zone      DMA      0      0      0      0      2      1      1      0  
   1      1      3
Node 0, zone    DMA32      5      5     10     20     15      5     16     16  
   9      4    700
Node 0, zone   Normal    344   1273   1414   1396   1047    473    143      0  
   0      0      0
```

Even though there's a lot of free memory in the system at the same times:

```
$ free -m
              total        used        free      shared  buff/cache   available
Mem:          11700        4897        3510          76        3293        5702
Swap:          2047           0        2047
```

I'm thinking about enforcing VM compaction every few minutes during the test
suite runs as a work around...

-- 
You are receiving this mail because:
You are the assignee for the bug.