[ https://issues.apache.org/jira/browse/LUCENE-1990?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12804062#action_12804062 ]
Paul Elschot commented on LUCENE-1990: -------------------------------------- Nice to see a more mature alternative. The trade off between (dummy element/unconditioned extra access) and (conditioned extra access) is of later concern. Both the extra access and the condition take cycles, so it's not clear which one will be faster. It might even depend on the value of elementBits. > Add unsigned packed int impls in oal.util > ----------------------------------------- > > Key: LUCENE-1990 > URL: https://issues.apache.org/jira/browse/LUCENE-1990 > Project: Lucene - Java > Issue Type: Improvement > Components: Index > Reporter: Michael McCandless > Priority: Minor > Attachments: LUCENE-1990-te20100122.patch, LUCENE-1990.patch, > LUCENE-1990_PerformanceMeasurements20100104.zip > > > There are various places in Lucene that could take advantage of an > efficient packed unsigned int/long impl. EG the terms dict index in > the standard codec in LUCENE-1458 could subsantially reduce it's RAM > usage. FieldCache.StringIndex could as well. And I think "load into > RAM" codecs like the one in TestExternalCodecs could use this too. > I'm picturing something very basic like: > {code} > interface PackedUnsignedLongs { > long get(long index); > void set(long index, long value); > } > {code} > Plus maybe an iterator for getting and maybe also for setting. If it > helps, most of the usages of this inside Lucene will be "write once" > so eg the set could make that an assumption/requirement. > And a factory somewhere: > {code} > PackedUnsignedLongs create(int count, long maxValue); > {code} > I think we should simply autogen the code (we can start from the > autogen code in LUCENE-1410), or, if there is an good existing impl > that has a compatible license that'd be great. > I don't have time near-term to do this... so if anyone has the itch, > please jump! -- This message is automatically generated by JIRA. - You can reply to this email to add a comment to the issue online. --------------------------------------------------------------------- To unsubscribe, e-mail: java-dev-unsubscr...@lucene.apache.org For additional commands, e-mail: java-dev-h...@lucene.apache.org