Does anyone know, or know where to find out, how long it takes to do a store to a device register on a Nahelem system with a PCIexpress device? Also, does write combining work with such a setup?
I recall that the QLogic Infinipath uses such features to get good short message performance, but my memory of it is pre- Nahelem. Question 2 - if the device stores to an address on which a core is spinning, how long does it take for the core to return the new value? These questions are to inform my thinking on PCIe device design. -Larry (Apologies if a duplicate with misspellings appears, I sent an earlier version from an off-list email.)
_______________________________________________ Beowulf mailing list, Beowulf@beowulf.org sponsored by Penguin Computing To change your subscription (digest mode or unsubscribe) visit http://www.beowulf.org/mailman/listinfo/beowulf
