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Posted to dev@jackrabbit.apache.org by "Marcel Reutegger (JIRA)" <ji...@apache.org> on 2011/09/06 10:32:09 UTC
[jira] [Created] (JCR-3065) ConcurrentModificationException in
FineGrainedISMLocking
ConcurrentModificationException in FineGrainedISMLocking
--------------------------------------------------------
Key: JCR-3065
URL: https://issues.apache.org/jira/browse/JCR-3065
Project: Jackrabbit Content Repository
Issue Type: Bug
Components: jackrabbit-core
Affects Versions: 2.2.0
Reporter: Marcel Reutegger
Assignee: Marcel Reutegger
Priority: Minor
Fix For: 2.3.0
We have a report where the FineGrainedISMLocking throws a ConcurrentModificationException (stacktrace
from a Jackrabbit 2.2.x):
java.util.ConcurrentModificationException
at java.util.HashMap$HashIterator.nextEntry(HashMap.java:793)
at java.util.HashMap$KeyIterator.next(HashMap.java:828)
at org.apache.jackrabbit.core.state.FineGrainedISMLocking$LockMap.hasDependency(FineGrainedISMLocking.java:388)
at org.apache.jackrabbit.core.state.FineGrainedISMLocking.acquireWriteLock(FineGrainedISMLocking.java:138)
at org.apache.jackrabbit.core.state.SharedItemStateManager.acquireWriteLock(SharedItemStateManager.java:1848)
at org.apache.jackrabbit.core.state.SharedItemStateManager.access$200(SharedItemStateManager.java:113)
at org.apache.jackrabbit.core.state.SharedItemStateManager$Update.begin(SharedItemStateManager.java:563)
at org.apache.jackrabbit.core.state.SharedItemStateManager.beginUpdate(SharedItemStateManager.java:1457)
at org.apache.jackrabbit.core.state.SharedItemStateManager.update(SharedItemStateManager.java:1487)
at org.apache.jackrabbit.core.state.LocalItemStateManager.update(LocalItemStateManager.java:351)
at org.apache.jackrabbit.core.state.XAItemStateManager.update(XAItemStateManager.java:354)
at org.apache.jackrabbit.core.state.LocalItemStateManager.update(LocalItemStateManager.java:326)
at org.apache.jackrabbit.core.state.SessionItemStateManager.update(SessionItemStateManager.java:289)
at org.apache.jackrabbit.core.ItemSaveOperation.perform(ItemSaveOperation.java:258)
at org.apache.jackrabbit.core.session.SessionState.perform(SessionState.java:200)
at org.apache.jackrabbit.core.ItemImpl.perform(ItemImpl.java:91)
at org.apache.jackrabbit.core.ItemImpl.save(ItemImpl.java:329)
at org.apache.jackrabbit.core.session.SessionSaveOperation.perform(SessionSaveOperation.java:42)
at org.apache.jackrabbit.core.session.SessionState.perform(SessionState.java:200)
at org.apache.jackrabbit.core.SessionImpl.perform(SessionImpl.java:355)
at org.apache.jackrabbit.core.SessionImpl.save(SessionImpl.java:758)
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[jira] [Commented] (JCR-3065) ConcurrentModificationException in
FineGrainedISMLocking
Posted by "Jukka Zitting (JIRA)" <ji...@apache.org>.
[ https://issues.apache.org/jira/browse/JCR-3065?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13097841#comment-13097841 ]
Jukka Zitting commented on JCR-3065:
------------------------------------
+1 Looks good.
One possible explanation for this is if we have multiple threads running inside the same transaction. Then the acquireReadLock() method could call the LockMap.addLock() method without acquiring the writeStateRWLock.
The logic behind the relevant TransactionContext code is that in some cases different parts of a transaction are performed by different threads, so locks acquired by one part should apply also to the other parts of the transaction. The assumption here is that even if something like that happens, the transaction manager should still ensure that only one thread at a time is executing within the scope of the transaction. Perhaps we should explicitly enforce that?
> ConcurrentModificationException in FineGrainedISMLocking
> --------------------------------------------------------
>
> Key: JCR-3065
> URL: https://issues.apache.org/jira/browse/JCR-3065
> Project: Jackrabbit Content Repository
> Issue Type: Bug
> Components: jackrabbit-core
> Affects Versions: 2.2.0
> Reporter: Marcel Reutegger
> Assignee: Marcel Reutegger
> Priority: Minor
> Fix For: 2.3.0
>
> Attachments: JCR-3065.patch
>
>
> We have a report where the FineGrainedISMLocking throws a ConcurrentModificationException (stacktrace
> from a Jackrabbit 2.2.x):
> java.util.ConcurrentModificationException
> at java.util.HashMap$HashIterator.nextEntry(HashMap.java:793)
> at java.util.HashMap$KeyIterator.next(HashMap.java:828)
> at org.apache.jackrabbit.core.state.FineGrainedISMLocking$LockMap.hasDependency(FineGrainedISMLocking.java:388)
> at org.apache.jackrabbit.core.state.FineGrainedISMLocking.acquireWriteLock(FineGrainedISMLocking.java:138)
> at org.apache.jackrabbit.core.state.SharedItemStateManager.acquireWriteLock(SharedItemStateManager.java:1848)
> at org.apache.jackrabbit.core.state.SharedItemStateManager.access$200(SharedItemStateManager.java:113)
> at org.apache.jackrabbit.core.state.SharedItemStateManager$Update.begin(SharedItemStateManager.java:563)
> at org.apache.jackrabbit.core.state.SharedItemStateManager.beginUpdate(SharedItemStateManager.java:1457)
> at org.apache.jackrabbit.core.state.SharedItemStateManager.update(SharedItemStateManager.java:1487)
> at org.apache.jackrabbit.core.state.LocalItemStateManager.update(LocalItemStateManager.java:351)
> at org.apache.jackrabbit.core.state.XAItemStateManager.update(XAItemStateManager.java:354)
> at org.apache.jackrabbit.core.state.LocalItemStateManager.update(LocalItemStateManager.java:326)
> at org.apache.jackrabbit.core.state.SessionItemStateManager.update(SessionItemStateManager.java:289)
> at org.apache.jackrabbit.core.ItemSaveOperation.perform(ItemSaveOperation.java:258)
> at org.apache.jackrabbit.core.session.SessionState.perform(SessionState.java:200)
> at org.apache.jackrabbit.core.ItemImpl.perform(ItemImpl.java:91)
> at org.apache.jackrabbit.core.ItemImpl.save(ItemImpl.java:329)
> at org.apache.jackrabbit.core.session.SessionSaveOperation.perform(SessionSaveOperation.java:42)
> at org.apache.jackrabbit.core.session.SessionState.perform(SessionState.java:200)
> at org.apache.jackrabbit.core.SessionImpl.perform(SessionImpl.java:355)
> at org.apache.jackrabbit.core.SessionImpl.save(SessionImpl.java:758)
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[jira] [Updated] (JCR-3065) ConcurrentModificationException in
FineGrainedISMLocking
Posted by "Marcel Reutegger (JIRA)" <ji...@apache.org>.
[ https://issues.apache.org/jira/browse/JCR-3065?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Marcel Reutegger updated JCR-3065:
----------------------------------
Attachment: JCR-3065.patch
Proposed patch.
> ConcurrentModificationException in FineGrainedISMLocking
> --------------------------------------------------------
>
> Key: JCR-3065
> URL: https://issues.apache.org/jira/browse/JCR-3065
> Project: Jackrabbit Content Repository
> Issue Type: Bug
> Components: jackrabbit-core
> Affects Versions: 2.2.0
> Reporter: Marcel Reutegger
> Assignee: Marcel Reutegger
> Priority: Minor
> Fix For: 2.3.0
>
> Attachments: JCR-3065.patch
>
>
> We have a report where the FineGrainedISMLocking throws a ConcurrentModificationException (stacktrace
> from a Jackrabbit 2.2.x):
> java.util.ConcurrentModificationException
> at java.util.HashMap$HashIterator.nextEntry(HashMap.java:793)
> at java.util.HashMap$KeyIterator.next(HashMap.java:828)
> at org.apache.jackrabbit.core.state.FineGrainedISMLocking$LockMap.hasDependency(FineGrainedISMLocking.java:388)
> at org.apache.jackrabbit.core.state.FineGrainedISMLocking.acquireWriteLock(FineGrainedISMLocking.java:138)
> at org.apache.jackrabbit.core.state.SharedItemStateManager.acquireWriteLock(SharedItemStateManager.java:1848)
> at org.apache.jackrabbit.core.state.SharedItemStateManager.access$200(SharedItemStateManager.java:113)
> at org.apache.jackrabbit.core.state.SharedItemStateManager$Update.begin(SharedItemStateManager.java:563)
> at org.apache.jackrabbit.core.state.SharedItemStateManager.beginUpdate(SharedItemStateManager.java:1457)
> at org.apache.jackrabbit.core.state.SharedItemStateManager.update(SharedItemStateManager.java:1487)
> at org.apache.jackrabbit.core.state.LocalItemStateManager.update(LocalItemStateManager.java:351)
> at org.apache.jackrabbit.core.state.XAItemStateManager.update(XAItemStateManager.java:354)
> at org.apache.jackrabbit.core.state.LocalItemStateManager.update(LocalItemStateManager.java:326)
> at org.apache.jackrabbit.core.state.SessionItemStateManager.update(SessionItemStateManager.java:289)
> at org.apache.jackrabbit.core.ItemSaveOperation.perform(ItemSaveOperation.java:258)
> at org.apache.jackrabbit.core.session.SessionState.perform(SessionState.java:200)
> at org.apache.jackrabbit.core.ItemImpl.perform(ItemImpl.java:91)
> at org.apache.jackrabbit.core.ItemImpl.save(ItemImpl.java:329)
> at org.apache.jackrabbit.core.session.SessionSaveOperation.perform(SessionSaveOperation.java:42)
> at org.apache.jackrabbit.core.session.SessionState.perform(SessionState.java:200)
> at org.apache.jackrabbit.core.SessionImpl.perform(SessionImpl.java:355)
> at org.apache.jackrabbit.core.SessionImpl.save(SessionImpl.java:758)
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[jira] [Resolved] (JCR-3065) ConcurrentModificationException in
FineGrainedISMLocking
Posted by "Marcel Reutegger (JIRA)" <ji...@apache.org>.
[ https://issues.apache.org/jira/browse/JCR-3065?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Marcel Reutegger resolved JCR-3065.
-----------------------------------
Resolution: Fixed
Committed patch in revision: 1165609
> ConcurrentModificationException in FineGrainedISMLocking
> --------------------------------------------------------
>
> Key: JCR-3065
> URL: https://issues.apache.org/jira/browse/JCR-3065
> Project: Jackrabbit Content Repository
> Issue Type: Bug
> Components: jackrabbit-core
> Affects Versions: 2.2.0
> Reporter: Marcel Reutegger
> Assignee: Marcel Reutegger
> Priority: Minor
> Fix For: 2.3.0
>
> Attachments: JCR-3065.patch
>
>
> We have a report where the FineGrainedISMLocking throws a ConcurrentModificationException (stacktrace
> from a Jackrabbit 2.2.x):
> java.util.ConcurrentModificationException
> at java.util.HashMap$HashIterator.nextEntry(HashMap.java:793)
> at java.util.HashMap$KeyIterator.next(HashMap.java:828)
> at org.apache.jackrabbit.core.state.FineGrainedISMLocking$LockMap.hasDependency(FineGrainedISMLocking.java:388)
> at org.apache.jackrabbit.core.state.FineGrainedISMLocking.acquireWriteLock(FineGrainedISMLocking.java:138)
> at org.apache.jackrabbit.core.state.SharedItemStateManager.acquireWriteLock(SharedItemStateManager.java:1848)
> at org.apache.jackrabbit.core.state.SharedItemStateManager.access$200(SharedItemStateManager.java:113)
> at org.apache.jackrabbit.core.state.SharedItemStateManager$Update.begin(SharedItemStateManager.java:563)
> at org.apache.jackrabbit.core.state.SharedItemStateManager.beginUpdate(SharedItemStateManager.java:1457)
> at org.apache.jackrabbit.core.state.SharedItemStateManager.update(SharedItemStateManager.java:1487)
> at org.apache.jackrabbit.core.state.LocalItemStateManager.update(LocalItemStateManager.java:351)
> at org.apache.jackrabbit.core.state.XAItemStateManager.update(XAItemStateManager.java:354)
> at org.apache.jackrabbit.core.state.LocalItemStateManager.update(LocalItemStateManager.java:326)
> at org.apache.jackrabbit.core.state.SessionItemStateManager.update(SessionItemStateManager.java:289)
> at org.apache.jackrabbit.core.ItemSaveOperation.perform(ItemSaveOperation.java:258)
> at org.apache.jackrabbit.core.session.SessionState.perform(SessionState.java:200)
> at org.apache.jackrabbit.core.ItemImpl.perform(ItemImpl.java:91)
> at org.apache.jackrabbit.core.ItemImpl.save(ItemImpl.java:329)
> at org.apache.jackrabbit.core.session.SessionSaveOperation.perform(SessionSaveOperation.java:42)
> at org.apache.jackrabbit.core.session.SessionState.perform(SessionState.java:200)
> at org.apache.jackrabbit.core.SessionImpl.perform(SessionImpl.java:355)
> at org.apache.jackrabbit.core.SessionImpl.save(SessionImpl.java:758)
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[jira] [Commented] (JCR-3065) ConcurrentModificationException in
FineGrainedISMLocking
Posted by "Marcel Reutegger (JIRA)" <ji...@apache.org>.
[ https://issues.apache.org/jira/browse/JCR-3065?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13097853#comment-13097853 ]
Marcel Reutegger commented on JCR-3065:
---------------------------------------
> [...] multiple threads running inside the same transaction.
I also noticed that this could be a potential problem, but in this case there is no transaction wrapped around the save call.
> ConcurrentModificationException in FineGrainedISMLocking
> --------------------------------------------------------
>
> Key: JCR-3065
> URL: https://issues.apache.org/jira/browse/JCR-3065
> Project: Jackrabbit Content Repository
> Issue Type: Bug
> Components: jackrabbit-core
> Affects Versions: 2.2.0
> Reporter: Marcel Reutegger
> Assignee: Marcel Reutegger
> Priority: Minor
> Fix For: 2.3.0
>
> Attachments: JCR-3065.patch
>
>
> We have a report where the FineGrainedISMLocking throws a ConcurrentModificationException (stacktrace
> from a Jackrabbit 2.2.x):
> java.util.ConcurrentModificationException
> at java.util.HashMap$HashIterator.nextEntry(HashMap.java:793)
> at java.util.HashMap$KeyIterator.next(HashMap.java:828)
> at org.apache.jackrabbit.core.state.FineGrainedISMLocking$LockMap.hasDependency(FineGrainedISMLocking.java:388)
> at org.apache.jackrabbit.core.state.FineGrainedISMLocking.acquireWriteLock(FineGrainedISMLocking.java:138)
> at org.apache.jackrabbit.core.state.SharedItemStateManager.acquireWriteLock(SharedItemStateManager.java:1848)
> at org.apache.jackrabbit.core.state.SharedItemStateManager.access$200(SharedItemStateManager.java:113)
> at org.apache.jackrabbit.core.state.SharedItemStateManager$Update.begin(SharedItemStateManager.java:563)
> at org.apache.jackrabbit.core.state.SharedItemStateManager.beginUpdate(SharedItemStateManager.java:1457)
> at org.apache.jackrabbit.core.state.SharedItemStateManager.update(SharedItemStateManager.java:1487)
> at org.apache.jackrabbit.core.state.LocalItemStateManager.update(LocalItemStateManager.java:351)
> at org.apache.jackrabbit.core.state.XAItemStateManager.update(XAItemStateManager.java:354)
> at org.apache.jackrabbit.core.state.LocalItemStateManager.update(LocalItemStateManager.java:326)
> at org.apache.jackrabbit.core.state.SessionItemStateManager.update(SessionItemStateManager.java:289)
> at org.apache.jackrabbit.core.ItemSaveOperation.perform(ItemSaveOperation.java:258)
> at org.apache.jackrabbit.core.session.SessionState.perform(SessionState.java:200)
> at org.apache.jackrabbit.core.ItemImpl.perform(ItemImpl.java:91)
> at org.apache.jackrabbit.core.ItemImpl.save(ItemImpl.java:329)
> at org.apache.jackrabbit.core.session.SessionSaveOperation.perform(SessionSaveOperation.java:42)
> at org.apache.jackrabbit.core.session.SessionState.perform(SessionState.java:200)
> at org.apache.jackrabbit.core.SessionImpl.perform(SessionImpl.java:355)
> at org.apache.jackrabbit.core.SessionImpl.save(SessionImpl.java:758)
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[jira] [Commented] (JCR-3065) ConcurrentModificationException in
FineGrainedISMLocking
Posted by "Marcel Reutegger (JIRA)" <ji...@apache.org>.
[ https://issues.apache.org/jira/browse/JCR-3065?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13097811#comment-13097811 ]
Marcel Reutegger commented on JCR-3065:
---------------------------------------
This is a bit unexpected and I don't have a test case to reproduce it. AFAICS the usage of the maps in the slots array of the
LockMap are properly protected by the writerStateRWLock.
I will additionally protect the maps with a synchronized block while looping over the key set.
> ConcurrentModificationException in FineGrainedISMLocking
> --------------------------------------------------------
>
> Key: JCR-3065
> URL: https://issues.apache.org/jira/browse/JCR-3065
> Project: Jackrabbit Content Repository
> Issue Type: Bug
> Components: jackrabbit-core
> Affects Versions: 2.2.0
> Reporter: Marcel Reutegger
> Assignee: Marcel Reutegger
> Priority: Minor
> Fix For: 2.3.0
>
>
> We have a report where the FineGrainedISMLocking throws a ConcurrentModificationException (stacktrace
> from a Jackrabbit 2.2.x):
> java.util.ConcurrentModificationException
> at java.util.HashMap$HashIterator.nextEntry(HashMap.java:793)
> at java.util.HashMap$KeyIterator.next(HashMap.java:828)
> at org.apache.jackrabbit.core.state.FineGrainedISMLocking$LockMap.hasDependency(FineGrainedISMLocking.java:388)
> at org.apache.jackrabbit.core.state.FineGrainedISMLocking.acquireWriteLock(FineGrainedISMLocking.java:138)
> at org.apache.jackrabbit.core.state.SharedItemStateManager.acquireWriteLock(SharedItemStateManager.java:1848)
> at org.apache.jackrabbit.core.state.SharedItemStateManager.access$200(SharedItemStateManager.java:113)
> at org.apache.jackrabbit.core.state.SharedItemStateManager$Update.begin(SharedItemStateManager.java:563)
> at org.apache.jackrabbit.core.state.SharedItemStateManager.beginUpdate(SharedItemStateManager.java:1457)
> at org.apache.jackrabbit.core.state.SharedItemStateManager.update(SharedItemStateManager.java:1487)
> at org.apache.jackrabbit.core.state.LocalItemStateManager.update(LocalItemStateManager.java:351)
> at org.apache.jackrabbit.core.state.XAItemStateManager.update(XAItemStateManager.java:354)
> at org.apache.jackrabbit.core.state.LocalItemStateManager.update(LocalItemStateManager.java:326)
> at org.apache.jackrabbit.core.state.SessionItemStateManager.update(SessionItemStateManager.java:289)
> at org.apache.jackrabbit.core.ItemSaveOperation.perform(ItemSaveOperation.java:258)
> at org.apache.jackrabbit.core.session.SessionState.perform(SessionState.java:200)
> at org.apache.jackrabbit.core.ItemImpl.perform(ItemImpl.java:91)
> at org.apache.jackrabbit.core.ItemImpl.save(ItemImpl.java:329)
> at org.apache.jackrabbit.core.session.SessionSaveOperation.perform(SessionSaveOperation.java:42)
> at org.apache.jackrabbit.core.session.SessionState.perform(SessionState.java:200)
> at org.apache.jackrabbit.core.SessionImpl.perform(SessionImpl.java:355)
> at org.apache.jackrabbit.core.SessionImpl.save(SessionImpl.java:758)
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[jira] [Updated] (JCR-3065) ConcurrentModificationException in
FineGrainedISMLocking
Posted by "Jukka Zitting (JIRA)" <ji...@apache.org>.
[ https://issues.apache.org/jira/browse/JCR-3065?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Jukka Zitting updated JCR-3065:
-------------------------------
Fix Version/s: (was: 2.3.0)
2.2.9
2.1.6
2.0.4
1.6.5
Merged to the 2.2 branch in revision 1174654, to 2.1 in 1174656, to 2.0 in 1174657, and to 1.6 in 1174659.
> ConcurrentModificationException in FineGrainedISMLocking
> --------------------------------------------------------
>
> Key: JCR-3065
> URL: https://issues.apache.org/jira/browse/JCR-3065
> Project: Jackrabbit Content Repository
> Issue Type: Bug
> Components: jackrabbit-core
> Affects Versions: 2.2.0
> Reporter: Marcel Reutegger
> Assignee: Marcel Reutegger
> Priority: Minor
> Fix For: 1.6.5, 2.0.4, 2.1.6, 2.2.9
>
> Attachments: JCR-3065.patch
>
>
> We have a report where the FineGrainedISMLocking throws a ConcurrentModificationException (stacktrace
> from a Jackrabbit 2.2.x):
> java.util.ConcurrentModificationException
> at java.util.HashMap$HashIterator.nextEntry(HashMap.java:793)
> at java.util.HashMap$KeyIterator.next(HashMap.java:828)
> at org.apache.jackrabbit.core.state.FineGrainedISMLocking$LockMap.hasDependency(FineGrainedISMLocking.java:388)
> at org.apache.jackrabbit.core.state.FineGrainedISMLocking.acquireWriteLock(FineGrainedISMLocking.java:138)
> at org.apache.jackrabbit.core.state.SharedItemStateManager.acquireWriteLock(SharedItemStateManager.java:1848)
> at org.apache.jackrabbit.core.state.SharedItemStateManager.access$200(SharedItemStateManager.java:113)
> at org.apache.jackrabbit.core.state.SharedItemStateManager$Update.begin(SharedItemStateManager.java:563)
> at org.apache.jackrabbit.core.state.SharedItemStateManager.beginUpdate(SharedItemStateManager.java:1457)
> at org.apache.jackrabbit.core.state.SharedItemStateManager.update(SharedItemStateManager.java:1487)
> at org.apache.jackrabbit.core.state.LocalItemStateManager.update(LocalItemStateManager.java:351)
> at org.apache.jackrabbit.core.state.XAItemStateManager.update(XAItemStateManager.java:354)
> at org.apache.jackrabbit.core.state.LocalItemStateManager.update(LocalItemStateManager.java:326)
> at org.apache.jackrabbit.core.state.SessionItemStateManager.update(SessionItemStateManager.java:289)
> at org.apache.jackrabbit.core.ItemSaveOperation.perform(ItemSaveOperation.java:258)
> at org.apache.jackrabbit.core.session.SessionState.perform(SessionState.java:200)
> at org.apache.jackrabbit.core.ItemImpl.perform(ItemImpl.java:91)
> at org.apache.jackrabbit.core.ItemImpl.save(ItemImpl.java:329)
> at org.apache.jackrabbit.core.session.SessionSaveOperation.perform(SessionSaveOperation.java:42)
> at org.apache.jackrabbit.core.session.SessionState.perform(SessionState.java:200)
> at org.apache.jackrabbit.core.SessionImpl.perform(SessionImpl.java:355)
> at org.apache.jackrabbit.core.SessionImpl.save(SessionImpl.java:758)
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