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https://issues.apache.org/jira/browse/IGNITE-12451?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16997909#comment-16997909
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Ivan Pavlukhin commented on IGNITE-12451:
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[~maliev], I would like to outline my main concerns here. When I saw a ticket
related to deadlock detection for ReentrantLock and friends, my first thought
was why already existing facilities cannot be used. Actually, I think that
having a note in a ticket description explaining why a custom implementation is
needed would be enough (and very good as well).
In general, a deadlock detection in any case will bring an additional overhead.
And I have doubts that it can be inexpensive.
By the way, we can consider other strategies for deadlocks mitigation. E.g. it
might be a deadlock _prevention_, it is simpler and perhaps fits current
problem.
> Introduce deadlock detection for cache entry reentrant locks
> ------------------------------------------------------------
>
> Key: IGNITE-12451
> URL: https://issues.apache.org/jira/browse/IGNITE-12451
> Project: Ignite
> Issue Type: Improvement
> Affects Versions: 2.7.6
> Reporter: Ivan Rakov
> Priority: Major
> Fix For: 2.9
>
>
> Aside from IGNITE-12365, we still have possible threat of cache-entry-level
> deadlock in case of careless usage of JCache mass operations (putAll,
> removeAll):
> 1. If two different user threads will perform putAll on the same two keys in
> reverse order (primary node for which is the same), there's a chance that
> sys-stripe threads will be deadlocked.
> 2. Even without direct contract violation from user side, HashMap can be
> passed as argument for putAll. Even if user threads have called mass
> operations with two keys in the same order, HashMap iteration order is not
> strictly defined, which may cause the same deadlock.
> Local deadlock detection should mitigate this issue. We can create a wrapper
> for ReentrantLock with logic that performs cycle detection in wait-for graph
> in case we are waiting for lock acquisition for too long. Exception will be
> thrown from one of the threads in such case, failing user operation, but
> letting the system make progress.
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