Re: verb spec clarification
Caitlin Bestler <[email protected]> Tue, 29 Mar 2005 06:38:34 -0800
| Newsgroups | gmane.ietf.rddp |
|---|---|
| Message-ID | <[email protected]> |
Culley, Paul wrote: > For Verbs, The answer is no. > > Section 7.6.3 pg 112 near top > "If the length of the access is zero, the RI MUST NOT perform any of the > above checks on the Memory Region." > > Section 7.10.6.2 pg 124, 2/3 down > "If the length of the access is zero, the RI MUST NOT perform any of the > above checks on the Memory Window." > > Paul R. Culley > HP Fellow > 281-514-5543 > Putting aside any overly broad use of the phrase "above checks", would you agree that the *only* thing special about zero length reads is that the STag is not validated? Specifically, the RDMA Read Response will still be ordered just as the response to any other RDMA Read Request, correct? Therefore, it will consume a resource (on either a connection or wider scale). That resource SHOULD/MUST be properly accounted for by *some* mechanism. I can think of nothing in the wire specifications that would justify suppressing of normal resource checking for zero length reads. The wire protocol does not specify *how* the local interface tracks resources, but the security draft requires that they be managed somehow whenever they are used across multiple connections or are in any way a resource more limited than just host memory.