Todd Lipcon has posted comments on this change. ( 
http://gerrit.cloudera.org:8080/11224 )

Change subject: IMPALA-7448: Invalidate recently unused tables from catalogd
......................................................................


Patch Set 3:

> Patch Set 3:
>
> This is also an essential feature for the old catalog (2.x branch).

Yep, this is important for both "v2" and "v1". I thought in general the 2.x 
branch is not getting new features, though.

> Haven't dug deeper, but I have a question that can we add a whitelist for 
> this eviction? It's expensive to load metadata of some huge tables, so it'd 
> be great if they can always being cached. Otherwise the first unlucky query 
> accessing these table will be stuck for a long time. To be simple, we can let 
> the whitelist configurable only in the startup options.

Unfortunately those huge tables also are the ones that take up the most memory, 
so there is the most benefit for evicting :) I guess a user-configurable way to 
prevent eviction would be useful but maybe we can add that as a follow-up 
instead of increasing the scope of this patch? One option might be to add a new 
table property, so the auto-invalidator skips tables when it sees something 
like "impala.pin_metadata" = "true"


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Gerrit-Project: Impala-ASF
Gerrit-Branch: master
Gerrit-MessageType: comment
Gerrit-Change-Id: Ib549717abefcffb14d9a3814ee8cf0de8bd49e89
Gerrit-Change-Number: 11224
Gerrit-PatchSet: 3
Gerrit-Owner: Tianyi Wang <[email protected]>
Gerrit-Reviewer: Andrew Sherman <[email protected]>
Gerrit-Reviewer: Impala Public Jenkins <[email protected]>
Gerrit-Reviewer: Quanlong Huang <[email protected]>
Gerrit-Reviewer: Tianyi Wang <[email protected]>
Gerrit-Reviewer: Todd Lipcon <[email protected]>
Gerrit-Reviewer: Vuk Ercegovac <[email protected]>
Gerrit-Comment-Date: Fri, 31 Aug 2018 17:55:57 +0000
Gerrit-HasComments: No

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