On Sat, Aug 18, 2018 at 2:12 AM Enrico Olivelli <eolive...@gmail.com> wrote:
> Nice work Sijie, > Some comments after the first read, just thinking out loud... > Overall looks a good idea and implementable. > > We should cite somewhere the case of scope=0 and ledgerId = -1 which is a > very special case for usthe. > For BC reason, negative ledger id are not supported when scope == 0. We effectively only support 63 bit. We can use versions on clients to distinguish whether they are old clients or new clients, then handle this case differently. So this special case should not be special for any new clients. We should also state that scopeid and ledgerid < 0 is not supported or it > is not clear to me how we will handle that case. > The case of scope < 0 is not clear to me as well, maybe I have to read more > carefully the doc. I think I answer this with my comment above. > > We are treating the global space of ledgerids as a 2 level hierarchy and > this is good for compatibility. > But thinking about a new application, which starts with uuids I think it > can be tricky, maybe we should add utilities/APIs to work with UUID > directly. The ledgerQualifiedName is the hex presentation of UUID, proposed to add to CLI tool. We can add it to API as well. However I would defer adding it until we need it or after we are on 128 bits. BC is the top concern. > For this new kind of application the space of ids would be flat and not > hierarchical (UUID are not hierarchical as far as I know, but I may be > wrong). In a lot of places, 128 bit is not well supported. So people would divide into two parts any way, msb and lsb. > > > We should also support listing the whole flat space Sure it can be added. I don’t see a reason we can’t. However IMO these are new features after we are on 128 bit. For the concerns in this BP, we are more focused on how we can transition from 64 bit to 128 bit. or as a last > alternative we should add a way to list the space of scopeids, because > otherwise the application must store the list of scopeids, and for it it > will be a set of half UUIDs. > > Thanks for driving this > > Enrico > > > > Il ven 17 ago 2018, 23:52 Venkateswara Rao Jujjuri <jujj...@gmail.com> ha > scritto: > > > Thanks a lot, Sijie for the awesome doc. > > Let's pool some more thoughts into this and size the work. > > > > Thanks, > > JV > > > > On Fri, Aug 17, 2018 at 2:36 PM, Sijie Guo <guosi...@gmail.com> wrote: > > > > > Hi all, > > > > > > As promised in last community meeting, I put up all the thoughts and > > > discussion with JV I had into a BP for supporting 128-bit ledger id. I > > > tried my best to cover all the aspects that I can think of. There can > be > > > places that I miss. so please take a look and let me know what you > think. > > > > > > BP PR: https://github.com/apache/bookkeeper/pull/1611 > > > Google doc: > > > https://docs.google.com/document/d/1cu54dNSV2ZrdWCi40LcyX8NxXGRCW > > > 0609T_ewmK9BWM > > > > > > - Sijie > > > > > > > > > > > -- > > Jvrao > > --- > > First they ignore you, then they laugh at you, then they fight you, then > > you win. - Mahatma Gandhi > > > -- > > > -- Enrico Olivelli >
