On 29 Aug 2013, at 16:51, Esteban Lorenzano <esteba...@gmail.com> wrote:
> hi > > well... I've never been happy on using the UUID generator for my keys, but is > the fastest option I found. > There are, of course, alternatives: > > 1) Using your own number generator (sequential, or whatever). Problem with > that is that is image based, then you need a persistence strategy... then you > are slow. > 2) then you can use your own procedure in mongo... with same problem than (1) > 3) you could use timestamp. but TimeStamps are slow :( > > anyway... I open to ideas :) > > in the mean time, you can check if your UUID generator is using the primitive > or not. In you are not, you have more possibilities of having a collision. Yes, the Smalltalk code (type 4 UUID) is just a random number that is computed in a complex way. What does the primitive actually do ? Is it different ? > Esteban > > On Aug 29, 2013, at 11:27 AM, Sabine Knöfel <sabine.knoe...@gmail.com> wrote: > >> Hi Esteban, All, >> >> I was proceeding to seach for the reason of the problem I described >> yesterday. >> >> I added some debugging code into VOMongoSerializer>>ensurePersisted: and the >> problem I described, did NOT occur. >> >> That made the whole process slower...and I had an idea.... >> >> I was looking into >>UUIDGenerator default makeSeed. >> Then I tried the following code: >> >> |theOld theNew| >> >> 100000000 timesRepeat: [ >> theNew := UUIDGenerator default makeSeed. >> theNew = theOld ifTrue: [self halt]. >> theOld := theNew] >> >> The debugger came up! Doesn't that mean that, if the code is run very fast, >> there are double OIDs generated?! >> >> In my case, the objects for country and currency are very lightweight and >> so, they are created very fast. Also, the error occured much more often >> within my fast production EC2 instance as at my (old and slow) development >> pc. >> >> Important: I work with windows and so >>makeUnixSeed returns nil... :-) >> >> What is your opinion about that? >> >> Sabine >> >> >> >> -- >> View this message in context: >> http://forum.world.st/voyage-mongo-randomly-wrong-OIDs-tp4705396p4705603.html >> Sent from the Pharo Smalltalk Users mailing list archive at Nabble.com. >> > >
