Re: hbase row locking

You didn't tell us which version of HBase. HBase is pretty smart about how long it needs to hold locks. For example the flush to the WAL is done without the row lock held. The row lock is only help to create the WAL edit and to add the edit to memstore, then it is released. After that we sync th

hbase row locking

Hello everyone, I have been running some experiments to see the effect of locking overhead in HBase. For this, I am comparing the throughput difference between these two schema. Schema1: rowkey-> columnkey-> cf: value-> blob of 2000 character Schema2: rowkey->: columnkey-> cf:order value-> blob

Pig HBase integration

Hi, We have a use case that involves ETL on data coming from several different sources using pig. We plan to store the final output table in HBase. What will be the performance impact if we do a join with an external CSV table using pig?. Regards, Krishna

Re: Trouble using copyTable to seed existing table to replication peer

Do any map-reduce jobs work on this cluster ? On Fri, Sep 26, 2014 at 5:13 PM, iain wright wrote: > Forgot to include the actual copy table command: > [hbase@master2 bin]$ ./hbase org.apache.hadoop.hbase.mapreduce.CopyTable > --starttime=1409128964 --peer.adr=master0.hbasex1.test.cloud.domain.tv

Re: Trouble using copyTable to seed existing table to replication peer

Forgot to include the actual copy table command: [hbase@master2 bin]$ ./hbase org.apache.hadoop.hbase.mapreduce.CopyTable --starttime=1409128964 --peer.adr=master0.hbasex1.test.cloud.domain.tv, master1.hbasex1.test.cloud.v.tv,master2.hbasex1.test.cloud.domain.tv:2181:/hbase moderation Replication

Trouble using copyTable to seed existing table to replication peer

Hi folks, I'm having trouble using copyTable to seed an existing tables data to a replication peer. Surely its an oversight in configuration on our part, but I've scoured the web and doc's for a couple days now. We have been able to run these jobs with success (perhaps they don't require localiza

[ANNOUNCE] Tephra 0.3.0 Release

Hi all, I'm happy to announce the 0.3.0 release of Tephra. This release is a renaming of the project from Continuuity Tephra to Cask Tephra, and includes the following changes: * All packages have changed from com.continuuity.tephra to co.cask.tephra * The Maven group ID has changed from com.con

Re: Region Server on all data node?

Prior to major compaction, region server may need to read HFile(s) written by other region server(s). This could be due to region movement, etc. Cheers On Fri, Sep 26, 2014 at 11:43 AM, Thomas Kwan wrote: > Thanks Ted for the pointer. A follow-up question. > > Will the region server always writ

Re: Region Server on all data node?

Thanks Ted for the pointer. A follow-up question. Will the region server always write data to its local hdfs? I am seeing logs that said the region server is trying to get data from another data nodes. Under what scenario will a region server needs to get data from a non-local data node? thanks

Re: A use case for ttl deletion?

This is a good writeup that should probably go to refguide. bq. example would be password reset attempts In some systems such information would have long retention period (maybe to conform to certain regulation). Cheers On Fri, Sep 26, 2014 at 9:10 AM, Wilm Schumacher wrote: > Hi, > > your ma

Re: A use case for ttl deletion?

Hi, your mail got me thinking about a general answer. I think a good answer would be: all data that are only usefull for a specific time AND are possibly generated infinitely for a finite number of users should have a ttl. OR when the space is very small compared to the number of users. An examp

Re: A use case for ttl deletion?

I wrote a cookie store for node.js using hbase. By this method the sessions are deleted "regularly" after a specific time nothing happens on a specific session. Am 26.09.2014 um 17:20 schrieb yonghu: > Hello, > > Can anyone give me a concrete use case for ttl deletions? I mean in which > situatio

A use case for ttl deletion?

Hello, Can anyone give me a concrete use case for ttl deletions? I mean in which situation we should set ttl property? regards! Yong

Re: Region Server on all data node?

Region server should be installed on server which is a data node. Region server count may be lower than data node count. So some data nodes would not have region server running. See http://hbase.apache.org/book.html#regions.arch.locality Cheers On Fri, Sep 26, 2014 at 7:02 AM, Thomas Kwan wrot

Region Server on all data node?

Hi there, To get good read performance, should the region server be installed on every data node? (Thinking about data locality here) thanks thomas