[
https://issues.apache.org/jira/browse/OAK-7860?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
Alex Deparvu updated OAK-7860:
------------------------------
Attachment: bench-trunk-10,50,100-crash at 50.png
> Make PermissionEntryCache more resilient against OOME
> -----------------------------------------------------
>
> Key: OAK-7860
> URL: https://issues.apache.org/jira/browse/OAK-7860
> Project: Jackrabbit Oak
> Issue Type: Improvement
> Components: core
> Reporter: Alex Deparvu
> Assignee: Alex Deparvu
> Priority: Major
> Fix For: 1.10, 1.9.10
>
> Attachments: bench-patch-1,5,10.png, bench-trunk-1,5,10.png,
> bench-trunk-10,50,100-crash at 50.png
>
>
> The PermissionEntryProviderImpl (one instance per session) is responsible for
> serving the permission entries. It can be backed by 2 different types of
> caches:
> * the {{PathEntryMapCache}} which is simply a map that eagerly loads all
> existing permissions for a session (aka. set of principals). Used only if
> there are less than 250 total entries per session (all principals combined).
> * The {{DefaultPermissionCache}} backed by the {{PermissionEntryCache}}. this
> is the fallback for the cases where the above is too expensive to use.
> In some cases, even if the number of permission entries per principal is not
> too large, a session that accumulates large numbers of group principals (I've
> seen over 700 in one internal case), will always fallback to use the
> {{PermissionEntryCache}}.
> The {{PermissionEntryCache}} is a cache that is using the principal as a key
> and the permission entries as values. It is aggregating 2 different types of
> data:
> * Existing policies: maps principals to paths with (their) existing policies
> (regular cache stuff)
> * but it also retains paths without any relevant policies for the current
> session, as empty sets [0]. being a cache keyed on the 'principal', this
> placeholder for empty policies will be set for each principal.
> I believe this second part can be responsible for a large memory footprint,
> which can also be amplified by the very large number of principals in the
> session.
> I would like to propose separating the 2 sets contained in the cache, putting
> the non-relevant paths in a dedicated map with a fixed size.
> [0]
> https://github.com/apache/jackrabbit-oak/blob/trunk/oak-core/src/main/java/org/apache/jackrabbit/oak/security/authorization/permission/PermissionEntryCache.java#L74
--
This message was sent by Atlassian JIRA
(v7.6.3#76005)
