libthr shared locks

[Daniel Eischen]

On Wed, 23 Dec 2015, John Baldwin wrote:

> On Wednesday, December 23, 2015 10:18:37 PM Konstantin Belousov wrote:
[ much snipped for brevity ]
>>
>> It is not feasible to do a reliable audit of the 24+ Kports.
>
> As a bit of a devil's advocate, I think the 64-bit ino_t change will in
> fact require this for 11.  I suspect 3rd pary apps embed struct stat in
> various structures as well and that that ABI change will require not
> mixing old and new libraries.
>
> One other point in favor of Konstantin's approach (IMO) is that keeping
> the structures private prevents having to maintain the ABI of those
> structures in the future.  I'm already keenly aware of how painful a
> problem that can be with our non-opaque FILE (and which we cannot now
> make opaque even though the standard APIs would work fine with an opaque
> object).

This seems to be David's latest patch:

   http://people.freebsd.org/~davidxu/patch/pshared0607.diff

It is only 3 years old (2012).  I have email from David that says
he got 8-10% speedup in mysql OLTP from making the synch types
structures.

The patch also implements robust and priority inheritence mutexes
bumps shared library versions.

-- 
DE