On Sep 27, 2007, at 22:16, Dustin Sallings write: > > On Sep 27, 2007, at 21:56, Paul Scott wrote: > > >> Agreed. Wouldnt it be great though to have a mem-based HA datastore? > > > > I would certainly vote +1 on that idea! > > You do realize you wouldn't have anything remotely like the > performance of memcached, don't you? You'd need something along the > lines of two-phase-commit if you want any kind of correctness. If > you don't want correctness, then why are you worried about HA? > We use memcached to store items fetched from a slow service, not from database. Performance difference between this service and memcached are huge. May be really convenient to have an HA feature on memcached servers.
> If you lose a node, how do you plan on rematerializing? A complete > synchronization would block both nodes in a two-node cluster. We've introduced libketama consistant hashing to reduce effects on server faults but it will be useful to have a redundant caching system between servers to be really fault toulerant. > > How would you handle conflicts during rematerialization after a > netsplit? > > Is it acceptable to block all clients during a netsplit (pending > some sort of magical synchronization that knows what to do when > conflicts occur)? > > After you get all of the pieces in place, are you sure you'd have > something that would be any faster than any solution that isn't > completely in-memory? > > -- > Dustin Sallings Michele -- Email.it, the professional e-mail, gratis per te: http://www.email.it/f Sponsor: Problemi di Liquidità? Con Logos Finanziaria 30.000 in 24 ore a dipendenti e lavoratori autonomi con rimborsi fino a 120 mesi clicca qui Clicca qui: http://adv.email.it/cgi-bin/foclick.cgi?mid=2907&d=20070928
