Re: Squid SMP on MacOS

On 25 February 2013 18:24, Alex Rousskov
<rousskov_at_measurement-factory.com> wrote:
> On 02/24/2013 10:02 PM, Amos Jeffries wrote:
>
>> I'm trying to get the MacOS builds of Squid going again but having some
>> problems with shm_open() in the Rock storage unit-tests.
>>
>> 1) MacOS defines the max name length we can pass to shm_open() at 30
>> bytes. "/squid-testRock__testRockSearch" being 35 or so bytes.
>> Cutting the definition in testRock.cc down so it becomes
>> "/squid-testRock_Search" resolves that, but then we hit (2).
>
> That TESTDIR name is wrong because it is used for more than just
> "search" testing. I bet the Rock name mimicked the UFS test name, but
> the UFS name is wrong too, for the same reason. We should use
> "cppUnitTestRock" and "cppUnitTestUfs" or something similarly unique and
> short, I guess.

We should use a random name; squidtest-10-bytes-of-entropy should do
it. Random because we don't want tests running in parallel to step on
each other on jenkins slaves.

>
>> 2) With the short string above and the current settings sent to
>> shm_open() in src/ipc/mem/Segment.cc line 73 MacOS shm_open() starts
>> responding with EINVAL.
>
>> theFD = shm_open(theName.termedBuf(), O_CREAT | O_RDWR | O_TRUNC,
>> S_IRUSR | S_IWUSR);
>
>
> Sounds like some of the five shm_open() flags we are using successfully
> elsewhere do not work on MacOS. I do not know which flag(s) do not work,
> and we have no MacOS boxes in the lab, so we cannot experiment or read
> documentation.
>
> I assume shared segment opening fails with similar symptoms when used
> outside of unit tests (e.g., with a shared memory cache)? If so, please
> feel free to disable shared memory support on MacOS (do not define
> HAVE_SHM?) until somebody who needs it can find the right combination of
> flags.

+1

-Rob

-- 
Robert Collins <rbtcollins_at_hp.com>
Distinguished Technologist
HP Cloud Services