[
https://issues.apache.org/jira/browse/IMPALA-9242?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17010800#comment-17010800
]
Csaba Ringhofer commented on IMPALA-9242:
-----------------------------------------
I looked through SENTRY-2539 (https://reviews.apache.org/r/71915) and the
related Impala code. Implementing IMPALA-9242 would need some significant
changes in Impala, especially if we want to avoid increasing memory usage.
The main issue is that Impala uses a (concurrent) hash set to store privileges
for a user/role, and the key contains all infos about a privilege, something
like
[ServerName=value]->[DbName=value]->[TableName=value]->[ColumnName=value]->[Action
Granted=value]->[Grant Option=value] ( see
https://github.com/apache/impala/blob/master/fe/src/main/java/org/apache/impala/catalog/PrincipalPrivilege.java
).
So this hash map doesn't offer a quick way to look up all privileges for a
given authorizable.
> Access check should only check against the privileges of the authorizable
> -------------------------------------------------------------------------
>
> Key: IMPALA-9242
> URL: https://issues.apache.org/jira/browse/IMPALA-9242
> Project: IMPALA
> Issue Type: Improvement
> Reporter: Vihang Karajgaonkar
> Assignee: Csaba Ringhofer
> Priority: Major
>
> Currently, according to the implementation of
> https://github.com/apache/sentry/blob/branch-2.1.0/sentry-provider/sentry-provider-cache/src/main/java/org/apache/sentry/provider/cache/SimpleCacheProviderBackend.java#L64
> each access check request in Sentry is done against all the privileges of the
> user. Instead, we can reduce the number of privilege checks significantly, if
> we use this API in
> https://github.com/apache/sentry/blob/master/sentry-provider/sentry-provider-cache/src/main/java/org/apache/sentry/provider/cache/PrivilegeCache.java#L46
> Unfortunately, SENTRY-1291 which is merged in master branch of Sentry is
> unavailable. However, if we can have a interface side changes in
> PrivilegeCache, Impala can implement a prefix-tree based {{PrivilegeCache}}
> so that number of privileges returned are only related to the given
> authorizable. This API can then be used in SimpleCacheProviderBackend to
> reduce the processing time required to check access for a large number of
> objects in large setups.
--
This message was sent by Atlassian Jira
(v8.3.4#803005)
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
