[ofa-general] Re: libmlx4 wc flash

[Roland Dreier]

 > Once the processor has started to evict data from the WC buffer into system
 > memory, it will make a bus-transaction style decision based on how much of the
 > buffer contains valid data. If the buffer is full (for example, all bytes are
 > valid) the processor will execute a burst-write transaction on the bus that
 > will result in all 32 bytes (P6 family processors) or 64 bytes (Pentium 4 and
 > Intel Xeon processor) being transmitted on the data bus in a single burst
 > transaction. If one or more of the WC buffer’s bytes are invalid (for example,
 > have not been written by software) then the processor will transmit the data to
 > memory using “partial write” transactions (one chunk at a time, where a “chunk”
 > is 8 bytes).

OK, thanks.

Do you have any idea how WC works on ppc?  Is the lwsync instruction
necessary/sufficient to flush WC buffers?

 - R.