Github user ramkrish86 commented on a diff in the pull request:
https://github.com/apache/phoenix/pull/8#discussion_r17045111
--- Diff:
phoenix-core/src/main/java/org/apache/phoenix/iterate/DefaultParallelIteratorRegionSplitter.java
---
@@ -138,14 +146,10 @@ public boolean apply(HRegionLocation location) {
// split each region in s splits such that:
// s = max(x) where s * x < t
//
- // The idea is to align splits with region boundaries. If rows are
not evenly
- // distributed across regions, using this scheme compensates for
regions that
- // have more rows than others, by applying tighter splits and
therefore spawning
- // off more scans over the overloaded regions.
- int splitsPerRegion = getSplitsPerRegion(regions.size());
// Create a multi-map of ServerName to List<KeyRange> which we'll
use to round robin from to ensure
// that we keep each region server busy for each query.
- ListMultimap<HRegionLocation,KeyRange> keyRangesPerRegion =
ArrayListMultimap.create(regions.size(),regions.size() * splitsPerRegion);;
+ int splitsPerRegion = getSplitsPerRegion(regions.size());
+ ListMultimap<HRegionLocation,KeyRange> keyRangesPerRegion =
ArrayListMultimap.create(regions.size(),regions.size() * splitsPerRegion);
if (splitsPerRegion == 1) {
for (HRegionLocation region : regions) {
--- End diff --
this will be a bit easier if the guideposts are sorted already
Ideally the guideposts should be sorted because we are inserting the
guideposts with the following rowkey - tablename, fam and regioname - so
considering there is only one fam those sets of guideposts would be sorted i
feel.
Another is, if the scan has to retrieve the row that is part of the
guidepost itself then the splits that we form from the guideposts, will
actually needs to be incremented by +1 (last byte) so that the upperrange of
the key range could be used as the stop row and will cover the exact row that
is as part of the guide posts.
---
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 [email protected] or file a JIRA ticket
with INFRA.
---
