Hello Quanlong Huang, Vihang Karajgaonkar, Impala Public Jenkins,

I'd like you to reexamine a change. Please visit

    http://gerrit.cloudera.org:8080/17298

to look at the new patch set (#17).

Change subject: IMPALA-10648: Invalidate catalogd table metadata cache for HMS 
DDL apis
......................................................................

IMPALA-10648: Invalidate catalogd table metadata cache for HMS DDL apis

For transactional tables, catalogd already guarantees consitent table
metadata reads based on the writeIdList passed in the request. For
non transactional tables, the reads are eventually consistent as in
event processor thread in the background, processes HMS events for the
table and updates its metadata.
In this patch, to ensure strong consistency guarantees for external
tables,we invalidate the table metadata from cache if HMS DDL apis
like alter/drop table/partition are accessed from catalogd's metastore
server. As a result of which, any subsequent get table request fetches
the table from HMS and loads it in cache. This ensures that any
get_table/get_partition requests after DDL operations on same table
return updated table metadata. This behavior has a performance penalty
since metadata loading in cache takes time specially for large tables.
The change is behind catalogd server's flag:
invalidate_hms_cache_on_ddls which is enabled by default. The flag
needs to be turned off in case of a performance bottleneck.

Change-Id: Idb9cc22ebfb51948433e4d57f4705ce201acaf98
---
M be/src/catalog/catalog-server.cc
M be/src/util/backend-gflag-util.cc
M common/thrift/BackendGflags.thrift
M 
fe/src/main/java/org/apache/impala/catalog/metastore/MetastoreServiceHandler.java
M fe/src/main/java/org/apache/impala/service/BackendConfig.java
M tests/custom_cluster/test_metastore_service.py
6 files changed, 604 insertions(+), 46 deletions(-)


  git pull ssh://gerrit.cloudera.org:29418/Impala-ASF refs/changes/98/17298/17
--
To view, visit http://gerrit.cloudera.org:8080/17298
To unsubscribe, visit http://gerrit.cloudera.org:8080/settings

Gerrit-Project: Impala-ASF
Gerrit-Branch: master
Gerrit-MessageType: newpatchset
Gerrit-Change-Id: Idb9cc22ebfb51948433e4d57f4705ce201acaf98
Gerrit-Change-Number: 17298
Gerrit-PatchSet: 17
Gerrit-Owner: Sourabh Goyal <soura...@cloudera.com>
Gerrit-Reviewer: Impala Public Jenkins <impala-public-jenk...@cloudera.com>
Gerrit-Reviewer: Quanlong Huang <huangquanl...@gmail.com>
Gerrit-Reviewer: Sourabh Goyal <soura...@cloudera.com>
Gerrit-Reviewer: Vihang Karajgaonkar <vih...@cloudera.com>

Reply via email to