Re: better atomics - v0.6
Oskari Saarenmaa <os@ohmu.fi>
From: Oskari Saarenmaa <os@ohmu.fi>
To: Andres Freund <andres@2ndquadrant.com>
Cc: Robert Haas <robertmhaas@gmail.com>,
Amit Kapila <amit.kapila16@gmail.com>,
Tom Lane <tgl@sss.pgh.pa.us>, Peter Geoghegan <pg@heroku.com>,
Pg Hackers <pgsql-hackers@postgresql.org>, Ants Aasma <ants@cybertec.at>
Date: 2014-09-23T21:27:25Z
Lists: pgsql-hackers
Attachments
- 0001-atomics-fix-atomic-add-for-sunpro-and-drop-invalid-e.patch (text/x-patch) patch 0001
23.09.2014, 15:18, Andres Freund kirjoitti: > On 2014-09-23 13:50:28 +0300, Oskari Saarenmaa wrote: >> 23.09.2014, 00:01, Andres Freund kirjoitti: >>> The patches: >>> 0001: The actual atomics API >> >> I tried building PG on Solaris 10/Sparc using GCC 4.9.0 (buildfarm animal >> dingo) with this patch but regression tests failed due to: > > Btw, if you could try sun studio it'd be great. I wrote the support for > it blindly, and I'd be surprised if I got it right on the first try. I just installed Solaris Studio 12.3 and tried compiling this: "../../../../src/include/port/atomics/generic-sunpro.h", line 54: return value type mismatch "../../../../src/include/port/atomics/generic-sunpro.h", line 77: return value type mismatch "../../../../src/include/port/atomics/generic-sunpro.h", line 79: #if-less #endif "../../../../src/include/port/atomics/generic-sunpro.h", line 81: #if-less #endif atomic_add_64 and atomic_add_32 don't return anything (the atomic_add_*_nv variants return the new value) and there were a few extra #endifs. Regression tests pass after applying the attached patch which defines PG_HAS_ATOMIC_ADD_FETCH_U32. There doesn't seem to be a fallback for defining pg_atomic_fetch_add based on pg_atomic_add_fetch so pg_atomic_add_fetch now gets implemented using pg_atomic_compare_exchange. Also, it's not possible to compile PG with FORCE_ATOMICS_BASED_SPINLOCKS with these patches: "../../../../src/include/storage/s_lock.h", line 868: #error: PostgreSQL does not have native spinlock support on this platform.... atomics/generic.h would implement atomic flags using operations exposed by atomics/generic-sunpro.h, but atomics/fallback.h is included before it and it defines functions for flag operations which s_lock.h doesn't want to use. / Oskari
Commits
-
Avoid the use of a separate spinlock to protect a LWLock's wait queue.
- 008608b9d510 9.6.0 cited
-
Improve LWLock scalability.
- ab5194e6f617 9.5.0 cited
-
Reduce the number of semaphores used under --disable-spinlocks.
- daa7527afc22 9.4.0 cited
-
Alter the configure script to fail immediately if the C compiler does not
- d15cb38dec01 9.0.0 cited