Cannot overwite and OutOfMemory during initial slurp kills crucible

Trying to import a new CVS repository - size on disk 92.2MB. Crucible ran for a long time (10's of mintutes, possibly hours), then locked up. It didn't die, but it was no longer accepting connections.

The last thing it logged was out of memory errors:

java.lang.OutOfMemoryError: Java heap space
ERROR - Exception during slurp
java.lang.OutOfMemoryError: Java heap space
ERROR - Exception during slurp
java.lang.OutOfMemoryError: Java heap space
ERROR - Exception during slurp
java.lang.OutOfMemoryError: Java heap space
ERROR - Exception during slurp
java.lang.OutOfMemoryError: Java heap space
ERROR - Exception during slurp
java.lang.OutOfMemoryError: Java heap space
ERROR - Exception during slurp
java.lang.OutOfMemoryError: Java heap space
ERROR - Exception during slurp
java.lang.OutOfMemoryError: Java heap space
Exception in thread "IncrementalPinger1" java.lang.OutOfMemoryError: Java heap s
pace
Exception in thread "btpool0-285" java.lang.OutOfMemoryError: Java heap space
Exception in thread "btpool0-1" java.lang.OutOfMemoryError: Java heap space

Before that, it had been complaining about not being able to overwrite some files, eg:

ERROR - problem with initial scan
com.cenqua.fisheye.rep.DbException: java.io.IOException: Cannot overwrite: D:\fi
sheye_home\var\cache\uecom\idx1_h3.tis
at com.cenqua.fisheye.lucene.LuceneConnection.withWriter(LuceneConnectio
n.java:331)
at com.cenqua.fisheye.cvsrep.cache.RepositoryIndex.indexContents(Reposit
oryIndex.java:74)
at com.cenqua.fisheye.cvsrep.cache.RepositoryIndex.indexFiles(Repository
Index.java:60)
at com.cenqua.fisheye.cvsrep.cache.CachedDirUpdater$BatchingIndexer.batc
hFlush(CachedDirUpdater.java:49)
at com.cenqua.fisheye.cvsrep.cache.CachedDirUpdater$BatchingIndexer.addT
oIndex(CachedDirUpdater.java:39)
at com.cenqua.fisheye.cvsrep.cache.CachedDirUpdater.recomputeDirInfo(Cac
hedDirUpdater.java:155)
at com.cenqua.fisheye.cvsrep.cache.CachedDirUpdater.scanPhase1(CachedDir
Updater.java:87)
at com.cenqua.fisheye.cvsrep.cache.CachedCvsRepositoryUpdater.scanDir(Ca
chedCvsRepositoryUpdater.java:247)
at com.cenqua.fisheye.cvsrep.cache.CachedCvsRepositoryUpdater.scanDirAnd
Files(CachedCvsRepositoryUpdater.java:221)
at com.cenqua.fisheye.cvsrep.cache.CachedCvsRepositoryUpdater.scanDirAnd
Files(CachedCvsRepositoryUpdater.java:229)
at com.cenqua.fisheye.cvsrep.cache.CachedCvsRepositoryUpdater.scanDirAnd
Files(CachedCvsRepositoryUpdater.java:229)
at com.cenqua.fisheye.cvsrep.cache.CachedCvsRepositoryUpdater.scanDirAnd
Files(CachedCvsRepositoryUpdater.java:229)
at com.cenqua.fisheye.cvsrep.cache.CachedCvsRepositoryUpdater.scanDirAnd
Files(CachedCvsRepositoryUpdater.java:229)
at com.cenqua.fisheye.cvsrep.cache.CachedCvsRepositoryUpdater.fullSlurp(
CachedCvsRepositoryUpdater.java:91)
at com.cenqua.fisheye.cvsrep.cache.CvsHistoryChangeDetector.doRunOnce(Cv
sHistoryChangeDetector.java:118)
at com.cenqua.fisheye.cvsrep.cache.CvsHistoryChangeDetector.ping(CvsHist
oryChangeDetector.java:53)
at com.cenqua.fisheye.cvsrep.cache.CachedCvsRepositoryUpdater.pingSlurp(
CachedCvsRepositoryUpdater.java:260)
at com.cenqua.fisheye.cvsrep.CvsRepositoryEngine.doSlurp(CvsRepositoryEn
gine.java:57)
at com.cenqua.fisheye.rep.ping.OneOffPingRequest.doRequest(OneOffPingReq
uest.java:30)

When I restarted Crucible, it started quickly, 10s of seconds or minutes, and has completed the initial scan and seems happy.