Re: Inefficient barriers on solaris with sun cc

On Fri, Sep 26, 2014 at 8:36 AM, Oskari Saarenmaa <os(at)ohmu(dot)fi> wrote:
> 25.09.2014, 16:34, Andres Freund kirjoitti:
>> Binaries compiled on solaris using sun studio cc currently don't have
>> compiler and memory barriers implemented. That means we fall back to
>> relatively slow generic implementations for those. Especially compiler,
>> read, write barriers will be much slower than necessary (since they all
>> just need to prevent compiler reordering as both sparc and x86 are run
>> in TSO mode under solaris).
>
> Attached patch implements compiler and memory barriers for Solaris Studio
> based on documentation at
> http://docs.oracle.com/cd/E18659_01/html/821-1383/gjzmf.html
>
> I defined read and write barriers as acquire and release barriers instead of
> pure read and write ones as that's what other platforms appear to do.

So you think a read barrier is the same thing as an acquire barrier
and a write barrier is the same as a release barrier? That would be
surprising. It's certainly not true in general.

--
Robert Haas
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