jackrabbit-oak-issues mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Marcel Reutegger (Jira)" <j...@apache.org>
Subject [jira] [Commented] (OAK-9112) High CPU IOWAIT on Mongo due to Oak Version Garbage Collection
Date Tue, 30 Jun 2020 12:53:00 GMT

    [ https://issues.apache.org/jira/browse/OAK-9112?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17148636#comment-17148636
] 

Marcel Reutegger commented on OAK-9112:
---------------------------------------

Thanks for the info. These calls appear to be legitimate Revision/Version GC calls. I don't
think these are related to the orderable child node issue you ran into. The high activity
by the Revision GC was probably just a coincidence.

> High CPU IOWAIT on Mongo due to Oak Version Garbage Collection
> --------------------------------------------------------------
>
>                 Key: OAK-9112
>                 URL: https://issues.apache.org/jira/browse/OAK-9112
>             Project: Jackrabbit Oak
>          Issue Type: Bug
>          Components: mongomk
>    Affects Versions: 1.8.22
>         Environment: Mongo: 3.4.9
> Hosteding: Scalegrid
> Instance Size: Small
>            Reporter: David Snowsill
>            Priority: Major
>         Attachments: image-2020-06-15-19-41-04-852.png, image-2020-06-15-19-41-40-385.png,
screenshot-1.png
>
>
> Over the previous weekend, our existing application went from having 100,000 documents
in the "nodes" collection to 600,000 documents in the "nodes" collection. Since that time
there appears to be an Oak background task that commences running near 100% CPU IOWAIT and
heavy disk activity (read only). Please refer to charts below
> !image-2020-06-15-19-41-04-852.png!
> !image-2020-06-15-19-41-40-385.png!
> According to currentOp Mongo command, the queries being running look as follows:
> {code}
> { desc: "conn4944", threadId: "140061124310784", connectionId: 4944, client: "18.207.114.70:47008",
clientMetadata: \{ driver: { name: "mongo-java-driver", version: "unknown" }, os: \{ type:
"Linux", name: "Linux", architecture: "amd64", version: "4.4.115-k8s" }, platform: "Java/IcedTea/1.8.0_212-b04"
}, active: true, opid: 2215767, secs_running: 2, microsecs_running: \{ "$numberLong": "2280333"
}, op: "query", ns: "prod-content-service.nodes", query: \{ find: "nodes", filter: { _id:
"2:/prod/18d6b4d0-9ee8-4a06-804e-b3669f67dda8" }, limit: 1, singleBatch: true }, planSummary:
"IDHACK", numYields: 0, locks: \{ Global: "r", Database: "r", Collection: "r" }, waitingForLock:
false, lockStats: \{ Global: { acquireCount: { r: { "$numberLong": "2" } } }, Database: \{
acquireCount: { r: { "$numberLong": "1" } } }, Collection: \{ acquireCount: { r: { "$numberLong":
"1" } } } } }
> {code}
> and appears to be iterating over the entire collection.
> Can anyone provide any guidance on what is happening?



--
This message was sent by Atlassian Jira
(v8.3.4#803005)

Mime
View raw message