Hi, What do you think about `.setFetchSize()` to 1 or a number small enough? This helps to avoid re-read and by the same time, the whole process requires only one connection to read from a table.
The cassandra documentation dis-encourage this practice because of its poor performance. But we're expecting a task to be taking really long. Vào Th 4, 19 thg 2, 2020 vào lúc 15:10 Tellier Benoit <btell...@apache.org> đã viết: > Hello Raphael, > > The simple fix could be : > > - 1. Iterating the in memory list of record > - 2. For each record, refresh it (re read it from DB to be sure to have > the latest version of it) > - 3. Then detect inconsistencies (reading the associated > denormalization table) > > Step 2., currently not implemented in [1], could be a way to mitigate > these risks. > > [1] Solving mailbox inconsistencies: > https://github.com/linagora/james-project/pull/3110 > > That way you decrease the concurrency window to the maximum. > > Cheers, > > Benoit > > On 18/02/2020 23:50, Raphaël Ouazana-Sustowski wrote: > > Hello, > > > > Is there a way to solve inconsistencies while not adding new ones? > > > > When you solve inconsistencies, you have a view of data in memory and > > try to fix it. If the data change between the moment you take this view > > and the moment you try to fix the inconsistency, you risk to add an > > other inconsistency, or worst to cancel a legitimate action. > > > > Do you see a way to mitigate this risk? > > > > Regards, > > > > Raphaël. > > > > Le 14/02/2020 à 11:06, Đức Trần Tiến a écrit : > >> Hello people, > >> > >> In recent days, James had been recieved a report about the strage > >> *MailboxNotFoundException*. There were some investigation to find the > >> cause > >> of the issue. > >> We found that there are some inconsistent between mailbox and > >> mailboxPathV2 > >> tables. The issue is considered critical and it and bother/annoying > users > >> to creates, rename, delete mailboxes. > >> I had open a PR for demonstrate this problem in unit test > >> https://github.com/linagora/james-project/pull/3100. There are some > taken > >> actions to be resolving the mailbox inconsistencies. > >> > >> But look back to the bigger picture, there're many tables have close > >> relationships, mailbox and mailboxPathV2 is just an example. There are > >> several proposals to prevent inconsistent but some have not been > >> discussed > >> further than an idea: > >> > >> - Introducing a *transaction* bounded with cassandra (it can > >> systematically resolve the issue) > >> - Re write the MailboxManager by *EventSourcing* > >> - Having tools to fix the already existing inconsistent > >> > >> *Having tools to fix the already existing inconsistent* > >> > >> We have: > >> - Webadmin Task for solving inconsistent cassandra mappings > >> - A self healing MessageFastViewProjections > >> > >> In developement: > >> - Webadmin Task for solving inconsistent mailbox & mailboxPath > >> - Retrying on failed mailbox creation/deletion > >> > >> I want to bring this conversation to the mailling list and hope that > >> we can > >> contribute solutions, enrich the proposals in order to reduce/fix the > >> cassandra inconsistencies. > >> > >> Thank you! > >> > >> Tran Tien Duc > >> > > > > --------------------------------------------------------------------- > > To unsubscribe, e-mail: server-dev-unsubscr...@james.apache.org > > For additional commands, e-mail: server-dev-h...@james.apache.org > > > > --------------------------------------------------------------------- > To unsubscribe, e-mail: server-dev-unsubscr...@james.apache.org > For additional commands, e-mail: server-dev-h...@james.apache.org > >
