[OpenAFS] replication over slower bandwidth

Simon Wilkinson simonxwilkinson@gmail.com
Sun, 12 Feb 2012 00:33:47 +0000

On 12 Feb 2012, at 00:02, muayad y wrote:

> when maxPacketSize has been uncommented, it did change  rx_connection =
struct behavoir,  rx_connection is being called on vos (userspace code)

The question is why this change actually improves performance - we need =
to understand that, so we can tell whether we also need to look at other =
structures and see if there are problems with them.

The question at the moment is whether this is a variable alignment issue =
(which would be surprising, as the x86_64 ABI specifies that all =
pointers should be aligned on 8 byte boundaries), or something more =
subtle, possibly related to cache line usage. The other possibility is =
that this is something entirely coincidental, not related to your code =
change at all. Further investigation is required.