Re: [PATCH] stdlib/test-bz22786: Avoid spurious test failures using alias mappings

[Rafal Luzynski <digitalfreak at lingonborough dot com>]

Florian,

Thank you for working on this.  I've just been struggling on finding the
correct TIMEOUT value for this test which was failing all the time on one
(only one!) of my devices.  I confirm that this patch applies, builds fine
and reduces the execution time from between 9 and 14 minutes (sic!) down
to about 3 seconds.

Please also see below:

26.10.2018 20:11 Florian Weimer <fweimer@redhat.com> wrote:
> 
> On systems without enough random-access memory, stdlib/test-bz22786
> will go deeply into swap and time out, even with a substantial
> TIMEOUTFACTOR.  This commit adds a facility to construct repeating

The macro is actually named TIMEOUT rather than TIMEOUTFACTOR.
Maybe you meant "TIMEOUT factor" or "TIMEOUT macro" or "TIMEOUT value"?

> strings with alias mappings, so that the requirement for physical
> memory, and uses it in stdlib/test-bz22786.
> 
> With 1 GiB RAM, execution time of the test goes from
> 
> 1.72user 5.68system 2:05.25elapsed 5%CPU (0avgtext+0avgdata
> 920932maxresident)k
> 8453744inputs+0outputs (131431major+1145697minor)pagefaults 0swaps

Can you please wrap the log comment at 76 column or below?

Did you mean this part to go to the commit comment?

> 
> down to:
> 
> 0.59user 0.37system 0:00.99elapsed 96%CPU (0avgtext+0avgdata
> 2097548maxresident)k
> 768inputs+8192outputs (4major+526458minor)pagefaults 0swaps

Same here.

> 2018-10-26  Florian Weimer  <fweimer@redhat.com>
> 
> 	Avoid spurious test failures in stdlib/test-bz22786.
> 	* support/Makefile (libsupport-routines): Add blob_repeat.
> 	(tests): Add tst-support_blob_repeat.
> 	* support/blob_repeat.h: New file.
> 	* support/blob_repeat.c: Likewise.
> 	* support/tst-support_blob_repeat.c: Likewise.
> 	* stdlib/test-bz22786.c (do_test): Replace malloc and memset with
> 	support_blob_repeat_allocate.
> [...]

Otherwise LGTM.

Regards,

Rafal