> On May 26, 2020, 11:48 p.m., Ashutosh Chauhan wrote: > > standalone-metastore/metastore-server/src/main/java/org/apache/hadoop/hive/metastore/Msck.java > > Lines 87-92 (original), 87-97 (patched) > > <https://reviews.apache.org/r/72521/diff/1/?file=2232456#file2232456line87> > > > > I don't follow how this is an improvement. new Configuration() which I > > assume is expensive call is still there. > > If anything, it appears that this change would make perf worse since > > earlier new Conf() was guarded by if (msc == null) so would have happened > > only once, but now will happen everytime. > > Can you explain how this change is more performant?
This is because, it was creating this for every table. With the fix in "PartitionManagementTask::run", patch constructs this conf only once and reuses it across tables. (i.e in Configuration msckConf = Msck.getMsckConf(conf);) - Rajesh ----------------------------------------------------------- This is an automatically generated e-mail. To reply, visit: https://reviews.apache.org/r/72521/#review220874 ----------------------------------------------------------- On May 18, 2020, 12:53 a.m., Rajesh Balamohan wrote: > > ----------------------------------------------------------- > This is an automatically generated e-mail. To reply, visit: > https://reviews.apache.org/r/72521/ > ----------------------------------------------------------- > > (Updated May 18, 2020, 12:53 a.m.) > > > Review request for hive, Ashutosh Chauhan and prasanthj. > > > Repository: hive-git > > > Description > ------- > > Msck.init for every table takes more CPU time than the actual table repair. > This was observed on a system which had lots of DB and tables. > > > Diffs > ----- > > ql/src/java/org/apache/hadoop/hive/ql/ddl/misc/msck/MsckOperation.java > c05d699bd8 > > ql/src/test/org/apache/hadoop/hive/ql/exec/TestMsckCreatePartitionsInBatches.java > 7821f40a82 > > ql/src/test/org/apache/hadoop/hive/ql/exec/TestMsckDropPartitionsInBatches.java > 8be31128a1 > > standalone-metastore/metastore-server/src/main/java/org/apache/hadoop/hive/metastore/Msck.java > f4e109d1b0 > > standalone-metastore/metastore-server/src/main/java/org/apache/hadoop/hive/metastore/PartitionManagementTask.java > e4488f4709 > > > Diff: https://reviews.apache.org/r/72521/diff/1/ > > > Testing > ------- > > > Thanks, > > Rajesh Balamohan > >
