From mboxrd@z Thu Jan 1 00:00:00 1970 Mime-Version: 1.0 (Apple Message framework v752.3) In-Reply-To: <13426df10711010904r317f9fd6v14a87dc2f024b0b1@mail.gmail.com> References: <317e48249cbfecef84062b5463b65b8d@plan9.bell-labs.com> <13426df10711010904r317f9fd6v14a87dc2f024b0b1@mail.gmail.com> Content-Type: text/plain; charset=US-ASCII; delsp=yes; format=flowed Message-Id: <852E4B7F-A64D-45AF-8FD3-9FD8F51D978B@lanl.gov> Content-Transfer-Encoding: 7bit From: Latchesar Ionkov Subject: Re: [9fans] QTCTL? Date: Thu, 1 Nov 2007 10:16:36 -0600 To: Fans of the OS Plan 9 from Bell Labs <9fans@cse.psu.edu> Topicbox-Message-UUID: e367a048-ead2-11e9-9d60-3106f5b1d025 Leases are good for purposes other than caching, for example locking. I don't see much difference if the protocol is going to define a special filename or a new message. There are other small details that need to be solved -- the server and the client need to be extra careful that no events fall between the cracks (i.e. between a Rread and the subsequent Tread on the special file). On Nov 1, 2007, at 10:04 AM, ron minnich wrote: > Why not just have a file that a client reads that lets the client know > of changes to files. > > client opens this server-provided file ("changes"? "dnotify"?) > > Server agrees to send client info about all FIDS which client has > active that are changing. Form of the message? > fid[4]offset[8]len[4] > > It's up to the client to figure out what to do. > > if the client doesn't care, no extra server overhead. > > no new T*, no callbacks (which i can tell you are horrible when you > get to bigger machines -- having an 'ls' take 30 minutes is no fun). > No leases. > > The fact is we have loose consistency now, we just don't call it that. > Anytime you are running a file from a server, you have loose > consistency. It works ok in most cases. > > ron