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https://issues.apache.org/jira/browse/IMPALA-12699?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17810533#comment-17810533
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Wenzhe Zhou commented on IMPALA-12699:
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There is only one client cache object for catalog service on each impalad,
which is created with FLAGS_catalog_client_rpc_timeout_ms as recv and send
timeout.
https://github.com/apache/impala/blob/cdac777c51febc99500b8426c2b3aabc7e9addd7/be/src/runtime/exec-env.cc#L224-L226
The catalog client cache object is initialized by calling
catalogd_client_cache_->InitMetrics(metrics_.get(), "catalog.server");
https://github.com/apache/impala/blob/cdac777c51febc99500b8426c2b3aabc7e9addd7/be/src/runtime/exec-env.cc#L430
If we want to apply a recv_timeout for GetPartialCatalogObject RPC only, then
we have to create a separate catalogd client cache object. How do we set
metrics for this additional client cache object? Currently the metrics names
are fixed.
https://github.com/apache/impala/blob/cdac777c51febc99500b8426c2b3aabc7e9addd7/be/src/runtime/client-cache.cc#L236-L249
Use a different key_prefix?
> Coordinator should retry GetPartialCatalogObject request and apply a recv
> timeout
> ---------------------------------------------------------------------------------
>
> Key: IMPALA-12699
> URL: https://issues.apache.org/jira/browse/IMPALA-12699
> Project: IMPALA
> Issue Type: Bug
> Components: Catalog
> Reporter: Quanlong Huang
> Assignee: Quanlong Huang
> Priority: Critical
>
> We have seen trivial GetPartialCatalogObject RPCs hanging in coordinator
> side, e.g. IMPALA-11409. Due to the piggyback mechanism of fetching metadata
> in local-catalog mode (see IMPALA-7534 or comments in
> CatalogdMetaProvider#loadWithCaching()), a hanging RPC on shared metadata
> (e.g. db list or table list of a db) could block other queries.
> We have also seen thrift RPCs hanging in IMPALA-3575. In fact,
> GetPartialCatalogObject RPCs are read-only requests. They can be cleanly
> retried. We should consider using a dedicated catalogd client cache for
> GetPartialCatalogObject requests and set an appropriate timeout for the
> socket.
> The current catalogd client cache:
> https://github.com/apache/impala/blob/cdac777c51febc99500b8426c2b3aabc7e9addd7/be/src/runtime/exec-env.cc#L224-L226
> The related flags:
> https://github.com/apache/impala/blob/cdac777c51febc99500b8426c2b3aabc7e9addd7/be/src/runtime/exec-env.cc#L161-L167
> CC [~wzhou]
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