On Thu, Oct 28, 2010 at 01:52:15PM +0200, Hans Schillstrom wrote: > Hello > > On Thursday 28 October 2010 13:35:12 Simon Horman wrote: > > On Wed, Oct 27, 2010 at 10:58:31PM +0300, Julian Anastasov wrote: > > > > > > Hello, > > > > > > On Wed, 27 Oct 2010, Hans Schillstrom wrote: > > > > > > >>A New Spec of Type field: > > > >> > > > >>Bit 7 6 . . . 2 1 0 > > > >> +----------+--------------------------+-------------+-------+ > > > >> | Opt.Data | Spare | Packed IPv6 | IPv6 | > > > >> +----------+--------------------------+-------------+-------+ > > > > > > > >I can see a better usage of it in Option Type so Type will look like this > > > > +-------------------------------------+-------------+-------+ > > > > | Spare | Packed IPv6 | IPv6 | > > > > +-------------------------------------+-------------+-------+ > > > > > > > >And "Option Type" in option field would look like this > > > > > > > >Bit 7 6 . . . 0 7 0 > > > > +----------+----------------------+---------------------------+ > > > > | Optional | Option type | Option length | > > > > +----------+----------------------+---------------------------+ > > > > As it stands a little more than 256 bytes may be needed for > > pe_data (+ pe_name_length + pe_name). This could be resolved by > > shortening the maximum pe_data length. Or perhaps we could use 16 bytes for > > Option length, which should ensure its never too small. > > > > The 256 byte limit that I made for pe_data was arbitrarily chosen. > > > > I have PE_NAME and PE_DATA ass different options > so the limit is actually 255 bytes. > > #define IPVS_OPT_SEQ_DATA 1 > #define IPVS_OPT_PE_DATA 2 > #define IPVS_OPT_PE_NAME 3 > > How ever they are not independant of each other. > - PE_NAME never goes alone, only if there is PE_DATA. > - In the receiving path, PE_NAME must have PE_DATA to be valid. Ok, thanks, I haven't reviewed the patches that closely yet :-( But still, 8 buts for option length does limit us to never ever having an option longer than 255 bytes. But I guess we can make sync protocol v3 if we need to cross that bridge. > > > >We can have a better fine tuning of options in this way. > > > > > > Yes, that is exactly my idea. I more like the name > > > "Parameter" instead of "Option", i.e. we have additional > > > parameters that can be mandatory (usually) but also can be > > > optional. For now I don't have idea for any optional > > > parameters but allocating 1 bit for this does not look > > > fatal. > > > > I'm not sure I understand the motivation for optional parameters. > > I think its important to allow for backwards compatibility. But > > I don't see that there will be multiple independent implementations > > of the synchronisation daemon in the near future. So the use-case > > isn't clear to me. > > Backward compatibility is "one way only" > a new backup daemon can listen to an old one > not the other way around. Yes. I thought that was my point :-) -- To unsubscribe from this list: send the line "unsubscribe lvs-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
