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Ohad Shacham commented on OMID-146: ----------------------------------- {quote}Also, will the commit cache be a problem now? As we run the CompactScanner, once we cache a commit ts as absent, we won't check it again, right? {quote} It is not a problem, since we cache a commit as absent only after invalidation. Which means that this transaction won't be able to commit anymore. This is basically needed only for the low latency mode. For the regular mode, we guarantee that the low water mark is persisted only after all the previous commit persisted and also transaction that started before the low water mark is aborted on commit request. > Persist transaction commit before updating low watermark > -------------------------------------------------------- > > Key: OMID-146 > URL: https://issues.apache.org/jira/browse/OMID-146 > Project: Apache Omid > Issue Type: Bug > Reporter: Ohad Shacham > Assignee: Yonatan Gottesman > Priority: Minor > Fix For: 1.0.1 > > Time Spent: 1h 10m > Remaining Estimate: 0h > > When a transaction t updates the conflict table at the TSO, it mights remove > entries of transactions that committed after t started, or even entries of t. > Therefore, in order to make sure that the garbage collector does not removes > entries of t from the data tables, thinking accidentally that t was not > committed yet. We should first persist t's commit in the commit table and > only then update the low watermark. This also applies to the low latency > which persists the commit by the clients. -- This message was sent by Atlassian JIRA (v7.6.3#76005)