Hi Tom I suspect I may be missing something here, but I think it's a pretty universal truism that cache lines are aligned to power-of-2 memory addresses, so it would suffice to ensure during setup that the lower order n bits of the object address are all zeros for each critical object; if the malloc() routine being used doesn't support that, it could be done by allocating a slightly larger than necessary block of memory and choosing a location within that.
The value of n could be architecture dependent, but n=8 would cover everyone, hopefully without wasting too much RAM. Cheers Dave On Tue, Dec 7, 2010 at 11:50 AM, Tom Lane <t...@sss.pgh.pa.us> wrote: > > One thing that might be interesting, but that I don't know how to attack > in a reasonably machine-independent way, is to try to ensure that shared > and local data structures don't accidentally overlap within cache lines. > When they do, you pay for fighting the cache line away from another > processor even when there's no real need. > > regards, tom lane > > -- > Sent via pgsql-performance mailing list (pgsql-performance@postgresql.org) > To make changes to your subscription: > http://www.postgresql.org/mailpref/pgsql-performance >
