Re: [PATCH 4.4 00/56] 4.4.98-stable review

[Guenter Roeck]

On Wed, Nov 15, 2017 at 04:17:19PM +0100, Greg Kroah-Hartman wrote:
> On Wed, Nov 15, 2017 at 05:45:41PM +0530, Naresh Kamboju wrote:
...
> > 
> > Please ignore this LTP readahead02 failure.
> > Re-tested and it got pass.
> > 
> > - cd /opt/ltp/testcases/bin/
> > - export TMPDIR=/home
> > - ./readahead02
> > 
> > readahead02    0  TINFO  :  creating test file of size: 67108864
> > readahead02    0  TINFO  :  read_testfile(0)
> > readahead02    0  TINFO  :  read_testfile(1)
> > readahead02    0  TINFO  :  readahead calls made: 16384
> > readahead02    1  TPASS  :  offset is still at 0 as expected
> > readahead02    0  TINFO  :  read_testfile(0) took: 973355 usec
> > readahead02    0  TINFO  :  read_testfile(1) took: 281199 usec
> > readahead02    0  TINFO  :  read_testfile(0) read: 67108864 bytes
> > readahead02    0  TINFO  :  read_testfile(1) read: 0 bytes
> > readahead02    2  TPASS  :  readahead saved some I/O
> > readahead02    0  TINFO  :  cache can hold at least: 364856 kB
> > readahead02    0  TINFO  :  read_testfile(0) used cache: 65252 kB
> > readahead02    0  TINFO  :  read_testfile(1) used cache: 65368 kB
> > readahead02    3  TPASS  :  using cache as expected
> 
> You all need to really fix up your testing systems... :(
> 
Hard lesson to learn. Tests are not as deterministic as we would like them
to be. For my part, I tend to re-run qemu tests before I report failures
because some failures are sporadic. After a couple of years I know the
usual suspects, which helps. Adding an automatic retry mechanism might
be useful.

Guenter