Ben Pfaff <b...@nicira.com> wrote on 01/09/2015 06:55:30 PM: > From: Ben Pfaff <b...@nicira.com> > To: Liran Schour/Haifa/IBM@IBMIL > Cc: dev <dev@openvswitch.org> > Date: 01/09/2015 06:55 PM > Subject: Re: OVN: RFC add a new JSON-RPC selective monitoring method > > On Mon, Aug 31, 2015 at 01:19:35PM +0300, Liran Schour wrote: > > Following the discussion on overcoming OVN scalability issues by allowing > > clients to monitor only rows that meet specific criteria > > (http://openvswitch.org/pipermail/dev/2015-August/059149.html), I propose > > to amend the OVSDB protocol specification (RFC 7047). > > > > Proposed amendment is to define a new monitor method, monitor_cond, for > > specifying monitoring conditions. Adding a new method allows keeping all > > of the existing client code intact, replacing code only in places that can > > benefit from this new method (e.g. in ovn-controller). > > > > Below is the description for a new JSON-RPC monitor_cond method to be > > added to the OVSDB protocol. (All references are to RFC 7047) > > Thanks. I have some comments. > > First, this drops the "columns" member. Why? I see no other way to > specify which columns are monitored. >
Will fix that. > Second, this isn't entirely clear about how to consider the conditions, > because a condition can be true before a row is modified and false > afterward, and vice versa. Presumably, when a row becomes covered by a > condition (after its initial insertion), or when a row is no longer > covered by a condition (even though it has not be deleted), the client > should be notified. > I will define it under the specification of <monitor_select>. > Third, this may be a good opportunity to fix a design mistake in > "monitor", which is that it sends too much data when a row is modified: > it sends both the old and new values for columns that have changed, as > well as the value of every column that did not change. I thought that > would be useful when I originally designed it, but it's proven to just > waste CPU and memory and bandwidth. > I will include a new version of Update Notification that will describe this change. I will re-write and send the proposal. Thanks, - Liran _______________________________________________ dev mailing list dev@openvswitch.org http://openvswitch.org/mailman/listinfo/dev
