[
https://issues.apache.org/jira/browse/LUCENE-5897?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14136439#comment-14136439
]
Steve Rowe commented on LUCENE-5897:
------------------------------------
LUCENE-5770 (JFlex 1.6 upgrade) happened in 4.10, so backporting to 4.9 will
require some changes.
> performance bug ("adversary") in StandardTokenizer
> --------------------------------------------------
>
> Key: LUCENE-5897
> URL: https://issues.apache.org/jira/browse/LUCENE-5897
> Project: Lucene - Core
> Issue Type: Bug
> Reporter: Robert Muir
> Assignee: Steve Rowe
> Fix For: 4.10, 5.0, 4.9.1
>
> Attachments: LUCENE-5897.patch
>
>
> There seem to be some conditions (I don't know how rare or what conditions)
> that cause StandardTokenizer to essentially hang on input: I havent looked
> hard yet, but as its essentially a DFA I think something wierd might be going
> on.
> An easy way to reproduce is with 1MB of underscores, it will just hang
> forever.
> {code}
> public void testWorthyAdversary() throws Exception {
> char buffer[] = new char[1024 * 1024];
> Arrays.fill(buffer, '_');
> int tokenCount = 0;
> Tokenizer ts = new StandardTokenizer();
> ts.setReader(new StringReader(new String(buffer)));
> ts.reset();
> while (ts.incrementToken()) {
> tokenCount++;
> }
> ts.end();
> ts.close();
> assertEquals(0, tokenCount);
> }
> {code}
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
---------------------------------------------------------------------
To unsubscribe, e-mail: dev-unsubscr...@lucene.apache.org
For additional commands, e-mail: dev-h...@lucene.apache.org
