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  • Jul 13 20:05

    rofr on v2

    move tests add azurite to test-deps test improvements and bugfixes … and 1 more (compare)

  • Jul 12 12:33

    rofr on v2

    failed file reader/writer synch… fix bug in new esdb reader (compare)

  • Jul 12 10:13

    rofr on ready-by-command

    failed file reader/writer synch… (compare)

  • Jul 10 15:47

    rofr on v2

    change .Result to GetAwaiter().… add appveyor test deps add test configuration (compare)

  • Jul 09 10:32

    rofr on v2

    Azure table storage WIP add taskextensions.cs use Fig for configuration and 9 more (compare)

  • Jun 30 21:26
    Build #13 passed
  • Jun 30 21:24

    rofr on master

    update test-dependencies script… Add options for SqlStreamStore … update nugets and core 2.1 -> 3… and 4 more (compare)

  • Jun 11 21:18
    Build #12 passed
  • Jun 11 21:15

    rofr on 0.7.11

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  • Jun 11 21:00
    Build #11 passed
  • Jun 11 20:21

    rofr on master

    disable performance test (compare)

  • Jun 11 20:08

    rofr on master

    disable pravega tests (compare)

  • Jun 11 19:57

    rofr on master

    update .NET Core 2.1 to 3.1, in… (compare)

  • Jun 02 06:55
    rofr commented #36
  • May 31 02:43
    Inux commented #36
  • May 26 21:40
    goblinfactory commented #76
  • May 22 21:57
    rofr labeled #112
  • May 22 21:57
    rofr opened #112
  • May 19 21:38

    rofr on master

    update nuget test deps Signed-… remove deprecated calls first implementation Pravega st… and 2 more (compare)

  • May 19 11:03
    Build #6 passed
Alan Hemmings
@goblinfactory
...ever the teacher.
Robert Friberg
@rofr
No, not teasing! Just trying to figure it out myself
Alan Hemmings
@goblinfactory
here' go try do this seamingly easy thing... because, when you finally give up, you'll be a whole lot wiser young padawan #yoda
hahah... if it's got the wise RF chin scratching, not sure how much I can help ...
I'm quite good at seeing narrow opportunities to hack things, ...just when folk are saying, ha... we can't use this library it's rubbish, it will give a collission one in every million requests due to foo or baa or "clock drift" ... and I see it could be perfect for gaming ...
or banking. would be a big improvement on the current banking systems accurancy! lol
Robert Friberg
@rofr
the problem here is bigger, we could miss records while reading the tail due to commands arriving with an oldish timestamp from a funky node
Alan Hemmings
@goblinfactory
that makes sense
Robert Friberg
@rofr
that would put is in the mongodb category :)
Alan Hemmings
@goblinfactory

I've found this while we were chatting which is either marketing bullshit, or possibly something we could use?

Azure Storage simplifies cloud development
The Azure storage service supports all three strategies, although it is distinctive in its ability to provide full support for optimistic and pessimistic concurrency because it was designed to embrace a > strong consistency model which guarantees that when the Storage service commits a data insert or update operation all further accesses to that data will see the latest update. Storage platforms
that use an eventual consistency model have a lag between when a write is performed by one user and when the updated data can be seen by other users thus complicating development of client > applications in order to prevent inconsistencies from affecting end users.

is that possibly good news?
Robert Friberg
@rofr
it won't help a late arriving record that get's inserted before other records because it has an older timestamp
Alan Hemmings
@goblinfactory
you mean problems like this ? cockroachdb/cockroach#13808
this sounds like ... if you can invent a protocol that could work around drift, you wouldnt have solved a big database problem, ...you'd have solved a big server clock problem, an even bigger market in terms of patent value?
Robert Friberg
@rofr
The problem remains even with perfectly synchronized clocks.
Alan Hemmings
@goblinfactory
if there was a work around for database folk, then the server clock manufacturers would use the same technique to improve their clocks.
Robert Friberg
@rofr
Memstate is not at all sensitive to the system time
Alan Hemmings
@goblinfactory
ok, I'll take the bait..."why does the problem still remain with perfectly syncrhonized clocks?" :D
Robert Friberg
@rofr
Latency.
Alan Hemmings
@goblinfactory
only if we're back to server generating the IDs
I may have misunderstood, ... your original suggestion that started this discussion was that we use reverse time ticks on clients, and add in a client ID?
Robert Friberg
@rofr
Well, if a node reads the tail and then a late arriving command is inserted then the read had a missing record
Alan Hemmings
@goblinfactory
so is that a non starter then? in order for it to be remotely possible, what building blocks are needed?
how have other tech offered what you'd like to see in memstate?
you have this already with cassandra right?
Robert Friberg
@rofr
Seems like a showstopper, yes. Anyway, I found an event sourcing implementation :)
Not cassandra
postgres, sqlstreamstore, eventstore are the main ones. Working on a provider for Pravega
Cosmos might work...
Alan Hemmings
@goblinfactory
I have that on my trello board for domanium to investigate
cant' remember how I found it.
Robert Friberg
@rofr
and the answer is....
drum roll.....
Alan Hemmings
@goblinfactory
Ah, just read the homepage docs and remember where I saw it... I had googled table storage limitations, and it came up in top results for the limitations
Robert Friberg
@rofr
optimistic concurrency!
Alan Hemmings
@goblinfactory
dont you still need to sort clock problem?
Robert Friberg
@rofr
Let's just build it on top of Streamstone, that will be simple
Alan Hemmings
@goblinfactory
tbh ... I don't care how it's sorted, I know it's complicated, and solutions involve complicated stuff like gossip protocols, ...stuff I really don't want to care about.
streamstone looks great, from what I saw.
ok... will throw something together tomorrow and compare that with single node, and see how they run...
assuming I don't ignore the compiler warnings ...
(groan!)
this will be fun :D
has been fun, except for... you know... the ...er... ignoring compiler warning thing.
Robert Friberg
@rofr
On top of StreamStone you won't need the BatchingJournalWriter, it already does batching
Alan Hemmings
@goblinfactory
Hi Rob, going to have to postpone eval of streamstone + memstate until this weekend. The big issue is not performance, but cost. Streamstone doesnt appear to support AzureTable storage, it only support Azure CosmosDb CloudTable which is similar but quite different cost wise.
I also probably won't be able to use it myself, since I need a solution that works with Azure functions, serverless style, that's pay as you go, with zero minimum monthly cost.