On Sat, Jun 25, 2011 at 6:02 AM, Mark Atwood <[email protected]> wrote: > Yes. It is the nature of the beast. Every time any thread hits any > mutex or other lock-like thing, every processor in the shared memory > space has to drain it's pipeline and sync all it's caches with memory. > They all have to do this, even if the lock isn't engaged. Just > checking it will do this. And, to make it even worse, the more > processors you have, more expensive this is to do.
AFAIK that's not true. Cache coherence mechanisms allow you to only 'sync' a tiny bit of address space. Olaf -- You received this bug notification because you are a member of UBUNTU - AL - BR, which is subscribed to Drizzle. https://bugs.launchpad.net/bugs/751191 Title: Global refresh_version not protected against races Status in A Lightweight SQL Database for Cloud Infrastructure and Web Applications: Fix Committed Bug description: Global var (g_)refresh_version is not protected against any races. To manage notifications about this bug go to: https://bugs.launchpad.net/drizzle/+bug/751191/+subscriptions -- Mailing list: https://launchpad.net/~linux-traipu Post to : [email protected] Unsubscribe : https://launchpad.net/~linux-traipu More help : https://help.launchpad.net/ListHelp
