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https://issues.apache.org/jira/browse/IGNITE-12451?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16997239#comment-16997239
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Mirza Aliev edited comment on IGNITE-12451 at 12/16/19 12:33 PM:
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[~Pavlukhin] I'm assuming that this note from javadoc of 
{{java.lang.management.ThreadMXBean#findDeadlockedThreads}} might be the reason 
to not use such approach.
{noformat}
This method is designed for troubleshooting use, but not for synchronization 
control. It might be an expensive operation.{noformat}
What do you think [~Pavlukhin] [~ivan.glukos]?


was (Author: maliev):
[~Pavlukhin] I'm assuming that these note from javadoc of 
{{java.lang.management.ThreadMXBean#findDeadlockedThreads}} might be the reason 
to not use such approach.
{noformat}
This method is designed for troubleshooting use, but not for synchronization 
control. It might be an expensive operation.{noformat}
What do you think [~Pavlukhin] [~ivan.glukos]?

> 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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