On Jun 2, 2010, at 5:38 AM, George Bosilca wrote: > I think adding support for sysv shared memory is a good thing. However, I > have some strong objections over the implementation in the hg tree. Here are > 2 of the major ones: > > 1) the sysv shared memory creation is __atomic__ based on the flags used. > Therefore, all the RML messages exchange is totally useless.
Not sure what you mean here. common/sm may create new shmem segments at any time (e.g., during coll sm). The RML message exchange is to ensure that only 1 process creates and initializes the segment and then all the others just attach to it. The initializing of the segment after it is created/attached could be pipelined a little more. E.g, since the init has an atomicly-set flag indicating when it's done, the root could create the seg, signal the others that they can attach, and then do the init -- the non-root procs can wait for flag to change atomicly to know when the seg has been initialized). Is that what you're referring to? > 2) the whole code is replicated in the 3 files (mmap, sysv and windows), even > the common parts. However in the sysv case most of the comments have been > modified to remove all capitals letter. I'm in favor of extracting all the > common parts and moving them in a special file. What should be kept in the > particular files should only be the really different parts (small part of the > init and finalize). Sam -- are the common parts really common? I.e., could they be factored out? Or are they "just different enough" that factoring them out would be a PITA? -- Jeff Squyres jsquy...@cisco.com For corporate legal information go to: http://www.cisco.com/web/about/doing_business/legal/cri/
