Github user dhutchis commented on a diff in the pull request:
https://github.com/apache/accumulo/pull/96#discussion_r60850768
--- Diff:
core/src/main/java/org/apache/accumulo/core/client/impl/TabletServerBatchReaderIterator.java
---
@@ -329,6 +331,8 @@ private void processFailures(Map<KeyExtent,List<Range>>
failures, ResultReceiver
// since the first call to binRanges clipped the ranges to within a
tablet, we should not get only
// bin to the set of failed tablets
+ if (!locator.isValid())
+ locator = new
TimeoutTabletLocator(TabletLocator.getLocator(instance, new Text(table)),
timeout);
--- End diff --
I see what you are saying @wjsl -- various QueryTask threads could
potentially read that their locators are not valid and then all replace the
locator. If n threads try to do this with unfortunate timing, then there are
n-1 creations of a new TimeoutTabletLocator that are thrown away. It's not a
particularly bad problem since the end result is correct no matter what, but it
would be nice to guard against it.
What do you think of this:
```java
if (!locator.isValid())
synchronized (TabletServerBatchReaderIterator.this) {
if (!locator.isValid())
locator = new TimeoutTabletLocator(TabletLocator.getLocator(instance,
new Text(table)), timeout);
}
```
I would do something similar for `ConditionalWriterImpl`. The
`TabletServerBatchWriter` is safe.
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