Will Berkeley created KUDU-2570:
-----------------------------------
Summary: Initialize rowset iterators lazily
Key: KUDU-2570
URL: https://issues.apache.org/jira/browse/KUDU-2570
Project: Kudu
Issue Type: Improvement
Components: tablet
Affects Versions: 1.7.1
Reporter: Will Berkeley
When a scan inits a tablet iterator, the tablet iterator inits iterator for
each rowset that is deemed relevant. When there's a lot of rowsets (usually
because of some missing feature like KUDU-1400 or a pathological partition
schema or configuration), this can take a long time, leading to scan timeouts
like
{noformat}
WARNINGS: Unable to open scanner: Timed out: Scan RPC to 10.1.11.187:7050 timedÂ
out after 169.988s (SENT){noformat}
For non-fault-tolerant scans, it seems like we should be able to init the
rowset when we first go to retrieve rows from, and thereby amortize all the
seeks to open rowsets across many ScanRequest RPC round trips.
For fault-tolerant scans, things are more complicated, but still it should be
possible to be lazier about initting rowset iterators.
--
This message was sent by Atlassian JIRA
(v7.6.3#76005)
