accumulo-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From ShawnWalker <>
Subject [GitHub] accumulo pull request: ACCUMULO-4229 BatchWriter Locator cache out...
Date Fri, 29 Apr 2016 15:41:26 GMT
Github user ShawnWalker commented on the pull request:
    Instead of trying to wrap things up so that these classes can pseudo-safely hold references
to instances of `TabletLocator`, I feel that it would be much simpler to establish the rule
"thou shalt not hold a reference to this for an extended period", and make changes appropriately.
    By which I mean:
    1. Refactor `ConditionalWriterImpl` to obtain a temporary `TabletLocator` reference at
the beginning of each method that needs it (`queue(...)`, `sendToServer(...)`, `invalidateSession(...)`),
instead of obtaining a single reference in the constructor.
    2. Modify `TimeoutTabletLocator` so that its constructor takes a `ClientContext` and a
tableId, like your current pull request already does.  But have each of it's methods invoke
`TabletLocator.getLocator(...)` anew.
    While I'm dubious that it'd be a real concern, if we felt that this would have significant
performance impact (due to lock contention), then it should be possible to partially ameliorate
the hit by using a Guava Cache or even a `ConcurrentHashMap`.

If your project is set up for it, you can reply to this email and have your
reply appear on GitHub as well. If your project does not have this feature
enabled and wishes so, or if the feature is enabled but not working, please
contact infrastructure at or file a JIRA ticket
with INFRA.

View raw message