hive-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Jim Green <openkbi...@gmail.com>
Subject Re: Reading tables will lock entire database in Hive 0.13
Date Thu, 26 Feb 2015 18:52:44 GMT
Hi Chaoyu,

Thanks for the information.
Actually by default, if we set hive.support.concurrency=true in Hive 0.13:
hive.lock.manager=org.apache.hadoop.hive.ql.lockmgr.zookeeper.ZooKeeperHiveLockManager
hive.txn.manager=org.apache.hadoop.hive.ql.lockmgr.DummyTxnManager

Hive-9199 mentioned it is fixed in 1.1, do you know if it will be fixed
under DummyTxnManager? Or does it mean it is fixed using new DbTxnManager?

Thanks.



On Thu, Feb 26, 2015 at 4:51 AM, Chaoyu Tang <ctang@cloudera.com> wrote:

> If you are using DummyTxnManager, please see HIVE-9199 which should
> resolve the issue.
>
> Thanks
>
> Chaoyu
>
> On Wed, Feb 25, 2015 at 11:57 PM, Alan Gates <alanfgates@gmail.com> wrote:
>
>> What lock manager are you using?
>>
>> Alan.
>>
>>   Jim Green <openkbinfo@gmail.com>
>>  February 25, 2015 at 17:24
>> Hi Team,
>>
>> Here is old thread about this issue:
>> http://qnalist.com/questions/5091386/doubt-about-locking-mechanism-in-hive
>>
>> I met the same issue that when reading one table in session A, we can not
>> create a table in the same database in session B. Basically it causes
>> database level lock in Hive 0.13 when hive.support.concurrency=true.
>>
>> Minimum reproduce:
>> --Session A:
>>
>> create table passwords (col0 string, col1 string, col2 string, col3
>> string, col4 string,
>> col5 string, col6 string) ROW FORMAT DELIMITED FIELDS TERMINATED BY ":";
>> load data local inpath "/etc/passwd" into table passwords;
>>
>> select count(*) from passwords a,passwords b, passwords c, passwords d
>> where a.col0=b.col0
>> and a.col0=c.col0
>> and a.col0=d.col0;
>>
>> --Session B:
>>
>> hive> create table test(id int);
>> conflicting lock present for default mode EXCLUSIVE
>>
>>
>> *Is this fixed or any jira related?*
>>
>> --
>> Thanks,
>> www.openkb.info
>> (Open KnowledgeBase for Hadoop/Database/OS/Network/Tool)
>>
>>
>


-- 
Thanks,
www.openkb.info
(Open KnowledgeBase for Hadoop/Database/OS/Network/Tool)

Mime
View raw message