On Mon, Sep 2, 2013 at 10:32 PM, Bruce Momjian <br...@momjian.us> wrote: > On Mon, Sep 2, 2013 at 10:14:03AM +0300, Heikki Linnakangas wrote: >> diff --git a/src/backend/access/transam/xlog.c >> b/src/backend/access/transam/xlog.c >> index 39c58d0..28e62ea 100644 >> --- a/src/backend/access/transam/xlog.c >> +++ b/src/backend/access/transam/xlog.c >> @@ -428,8 +428,14 @@ typedef struct XLogCtlInsert >> uint64 CurrBytePos; >> uint64 PrevBytePos; >> >> - /* insertion slots, see above for details */ >> - XLogInsertSlotPadded *insertSlots; >> + /* >> + * Make sure the above heavily-contended spinlock and byte positions >> are >> + * on their own cache line. In particular, the RedoRecPtr and full page >> + * write variables below should be on a different cache line. They are >> + * read on every WAL insertion, but updated rarely, and we don't want >> + * those reads to steal the cache line containing Curr/PrevBytePos. >> + */ >> + char pad[128]; > > Do we adjust for cache line lengths anywhere else? PGPROC? Should it > be a global define?
+1 -- that is, I think it should be. merlin -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
