[Exist-open] Deadlock

[Etienne B. <eb...@fu...>]

Hi,

I'm using 20040123 snapshot, in embedded mode (in a webapp environment).
I get a snapshot when I have a thread heavily inserting nodes into
eXist and another one executing a query. Here is the thread
dump (an excerpt) :

Full thread dump Java HotSpot(TM) Client VM (1.4.2_03-b02 mixed mode):

"ApplicationServerThread" prio=3D1 tid=3D0x080d16b8 nid=3D0x63f0 in Object.=
wait() [517f9000..517fa8bc]
        at java.lang.Object.wait(Native Method)
        - waiting on <0x468d5588> (a org.exist.util.ReentrantReadWriteLock)
        at org.exist.util.ReentrantReadWriteLock.acquire(ReentrantReadWrite=
Lock.java:64)
        - locked <0x468d5588> (a org.exist.util.ReentrantReadWriteLock)
        at org.exist.storage.NativeBroker.getCollection(NativeBroker.java:4=
92)
        at org.exist.collections.Collection.allDocs(Collection.java:222)
        at org.exist.collections.Collection.allDocs(Collection.java:208)
        - locked <0x46acc718> (a org.exist.collections.Collection)
        at org.exist.storage.NativeBroker.getDocumentsByCollection(NativeBr=
oker.java:608)
        at org.exist.parser.Util.createFunction(Util.java:86)
        at org.exist.parser.XPathTreeParser2.functionCall(XPathTreeParser2.=
java:1383)
        at org.exist.parser.XPathTreeParser2.pathExpr(XPathTreeParser2.java=
:555)
        at org.exist.parser.XPathTreeParser2.pathExpr(XPathTreeParser2.java=
:859)
        at org.exist.parser.XPathTreeParser2.expr(XPathTreeParser2.java:418)
        at org.exist.parser.XPathTreeParser2.xpath(XPathTreeParser2.java:44=
9)
        at org.exist.xmldb.LocalXPathQueryService.doQuery(LocalXPathQuerySe=
rvice.java:118)
        at org.exist.xmldb.LocalXPathQueryService.query(LocalXPathQueryServ=
ice.java:83)
        at org.exist.xmldb.LocalXPathQueryService.query(LocalXPathQueryServ=
ice.java:69)
        at com.fullsix.edito.impl.XMLDBManager.query(XMLDBManager.java:440)
        at com.fullsix.edito.impl.ContentQueryImpl.run(ContentQueryImpl.jav=
a:75)
	at com.fullsix.edito.admin.FolderTree.buildTree(FolderTree.java:79)
        at com.fullsix.edito.admin.FolderTree.getTree(FolderTree.java:52)
        - locked <0x451b0be0> (a java.util.Collections$SynchronizedMap)
        at com.fullsix.edito.admin.NodesTreeAction.performAction(NodesTreeA=
ction.java:92)
        at com.fullsix.edito.admin.BaseAction.execute(BaseAction.java:95)
        at org.apache.struts.action.RequestProcessor.processActionPerform(R=
equestProcessor.java:484)
        at org.apache.struts.action.RequestProcessor.process(RequestProcess=
or.java:274)
        at org.apache.struts.action.ActionServlet.process(ActionServlet.jav=
a:1482)
        at org.apache.struts.action.ActionServlet.doGet(ActionServlet.java:=
507)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:195)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:309)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:336)
        at com.evermind._csb._phd(.:518)
        at com.evermind._csb._bkc(.:174)
        at com.evermind._ax._lpc(.:620)
        at com.evermind._ax._tzb(.:189)
        at com.evermind._bf.run(.:62)
        - locked <0x46a10898> (a com.evermind.server.ApplicationServerThrea=
d)

[...]

"WorkerThread-1" prio=3D1 tid=3D0x080cee08 nid=3D0x63f0 waiting for monitor=
 entry [527be000..527be8bc]
        at org.exist.collections.Collection.setBroker(Collection.java:331)
        - waiting to lock <0x46acc718> (a org.exist.collections.Collection)
        at org.exist.storage.NativeBroker.getCollection(NativeBroker.java:4=
95)
        at org.exist.storage.NativeBroker.getCollection(NativeBroker.java:4=
60)
        at org.exist.collections.Collection.getParent(Collection.java:318)
        - locked <0x46abbe00> (a org.exist.collections.Collection)
        at org.exist.storage.NativeBroker.saveCollection(NativeBroker.java:=
1552)
        at org.exist.storage.NativeBroker.saveCollection(NativeBroker.java:=
1554)
        at org.exist.storage.NativeBroker.addDocument(NativeBroker.java:150=
9)
        at org.exist.Parser.store(Parser.java:994)
        at org.exist.Parser.parse(Parser.java:462)
        at org.exist.xmldb.LocalCollection.storeResource(LocalCollection.ja=
va:406)
        at com.fullsix.edito.impl.XMLDBManager.storeXMLDocument(XMLDBManage=
r.java:100)
        at com.fullsix.edito.impl.XMLDBManager.storeXMLDocument(XMLDBManage=
r.java:57)
        at com.fullsix.edito.jobs.SyncXMLDbJob.process(SyncXMLDbJob.java:99)
        at com.fullsix.edito.jobs.SyncXMLDbJob.execute(SyncXMLDbJob.java:13=
8)
        at org.quartz.core.JobRunShell.run(JobRunShell.java:147)
        at org.quartz.simpl.SimpleThreadPool$WorkerThread.run(SimpleThreadP=
ool.java:386)

The "ApplicationServerThread" is the one that makes the xpath query.
The WorkerThread-1 is a thread than inserts a lot of documents and
creates many collections.

I've got the problem when I perform a xupdate during a massive
insertion too.

Tell me if you need more information. I had no such problem with
previous versions (I have not tested all the snapshots, though).
--=20
Etienne Bernard <eb...@fu...>
Senior Software Engineer - FullSIX - http://www.fullsix.com/