[
https://issues.apache.org/jira/browse/IGNITE-4766?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
Vladimir Ozerov closed IGNITE-4766.
-----------------------------------
> Relax worker thread wakeup logic in StipedExecutor
> --------------------------------------------------
>
> Key: IGNITE-4766
> URL: https://issues.apache.org/jira/browse/IGNITE-4766
> Project: Ignite
> Issue Type: Task
> Components: general
> Affects Versions: 1.9
> Reporter: Vladimir Ozerov
> Assignee: Vladimir Ozerov
> Fix For: 2.1
>
> Attachments: IGNITE_4766.patch
>
>
> *Problem*
> Worker threads in {{StripedExecutor}} have {{parked}} state flag. When set to
> {{true}} NIO threads will call {{LockSupport.unpark}} after submitting new
> task to a queue.
> The problem is that this flag is only changed by worker thread. Thus, if NIO
> worker submitted a new task and called {{unpark}}, worker will clean up
> {{parked}} state only after real wake up what may take microseconds. All
> subsequent submits from NIO thread occurred during this time will also invoke
> {{unpark}} thus generating high contention on the underlying OS primitives.
> Namely, condition variables which ultimately delegates to {{futex}} on Linux.
> *Solution*
> NIO threads must be able to clear {{parked}} state as well. Some CAS magic
> will be required there. This way we will minimize number of {{unapark}} calls.
--
This message was sent by Atlassian JIRA
(v6.3.15#6346)
