Messages in this thread |  | | | Date | Thu, 14 Feb 2008 10:23:23 -0600 | | From | Steve Wise <> | | Subject | Re: [ofa-general] Re: Demand paging for memory regions |
| |
Robin Holt wrote: > On Thu, Feb 14, 2008 at 09:09:08AM -0600, Steve Wise wrote: >> Note that for T3, this involves suspending _all_ rdma connections that are >> in the same PD as the MR being remapped. This is because the driver >> doesn't know who the application advertised the rkey/stag to. So without > > Is there a reason the driver can not track these. >
Because advertising of a MR (ie telling the peer about your rkey/stag, offset and length) is application-specific and can be done out of band, or in band as simple SEND/RECV payload. Either way, the driver has no way of tracking this because the protocol used is application-specific.
>> Point being, it will stop probably all connections that an application is >> using (assuming the application uses a single PD). > > It seems like the need to not stop all would be a compelling enough reason > to modify the driver to track which processes have received the rkey/stag. >
Yes, _if_ the driver could track this.
And _if_ the rdma API and paradigm was such that the kernel/driver could keep track, then remote revokations of MR tags could be supported.
Stevo
|  |