increase usage of "unfilled" pages after successful committed deleted purged
rows.
----------------------------------------------------------------------------------
Key: DERBY-1193
URL: http://issues.apache.org/jira/browse/DERBY-1193
Project: Derby
Type: Improvement
Components: Store
Versions: 10.1.2.3
Reporter: Mike Matrigali
Priority: Minor
The current system is pretty pessimistic about setting the "unfilled" state on
a page. It seems like any time a row is purged from
a page the page state could be set to unfilled as it is likely another row in
the same table may now fit on the page. This may be
too simple, maybe some number greater than 1, or some comparison to the average
row length of the rows in the table, or maybe
maximum row length.
The downside to setting unfilled optimistically is possible extra overhead on
subsequent inserts. It is a space vs. performance
tradeoff.
Minimally purges done in the first phase of compress, should set unfilled so
that defragment phase can have more opportunity to
reclaim space.
--
This message is automatically generated by JIRA.
-
If you think it was sent incorrectly contact one of the administrators:
http://issues.apache.org/jira/secure/Administrators.jspa
-
For more information on JIRA, see:
http://www.atlassian.com/software/jira
