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From Manjeet Singh <manjeet.chand...@gmail.com>
Subject Re: Hbase Row key lock
Date Sun, 23 Oct 2016 19:02:17 GMT
Till now what i understand their is no update

if two different thread try to update same record what happen

first record insert with some version
second thread comes and change the version and its like a new insert with
some version
this process called MVCC

If I am correct how hbase support MVCC mean any configuration for handlling
multiple thread at same time?

On Mon, Oct 24, 2016 at 12:24 AM, Manjeet Singh <manjeet.chandhok@gmail.com>
wrote:

> No I don't have 50 clients? I want to understand internal working of Hbase
> in my usecase I have bulk update operation from spark job we have 7
> different kafka pipeline and 7 spark job
> it might happen that my 2 0r 3 spark job have same rowkey for update
>
>
>
> On Mon, Oct 24, 2016 at 12:20 AM, Dima Spivak <dimaspivak@apache.org>
> wrote:
>
>> If your typical use case sees 50 clients simultaneously trying to update
>> the same row, then a strongly consistent data store that writes to disk
>> for
>> fault tolerance may not be for you. That said, such a use case seems
>> extremely unusual to me and I'd ask why you're trying to update the same
>> row in such a manner.
>>
>> On Sunday, October 23, 2016, Manjeet Singh <manjeet.chandhok@gmail.com>
>> wrote:
>>
>> > Hi Dima,
>> >
>> > I didn't get ? point is assume I have 50 different client all having
>> same
>> > rowkey all want to update on same rowkey at same time now just tell what
>> > will happen? who will get what value?
>> >
>> > Thanks
>> > Manjeet
>> >
>> > On Mon, Oct 24, 2016 at 12:12 AM, Dima Spivak <dimaspivak@apache.org
>> > <javascript:;>> wrote:
>> >
>> > > Unless told not to, HBase will always write to memory and append to
>> the
>> > WAL
>> > > on disk before returning and saying the write succeeded. That's by
>> design
>> > > and the same write pattern that companies like Apple and Facebook have
>> > > found works for them at scale. So what's there to solve?
>> > >
>> > > On Sunday, October 23, 2016, Manjeet Singh <
>> manjeet.chandhok@gmail.com
>> > <javascript:;>>
>> > > wrote:
>> > >
>> > > > Hi All,
>> > > >
>> > > > I have read below mention blog and it also said Hbase holds the
>> lock on
>> > > > rowkey level
>> > > > https://blogs.apache.org/hbase/entry/apache_hbase_
>> > internals_locking_and
>> > > > (0) Obtain Row Lock
>> > > > (1) Write to Write-Ahead-Log (WAL)
>> > > > (2) Update MemStore: write each cell to the memstore
>> > > > (3) Release Row Lock
>> > > >
>> > > >
>> > > > SO question is how to solve this if I have very frequent update on
>> > Hbase
>> > > >
>> > > > Thanks
>> > > > Manjeet
>> > > >
>> > > > On Wed, Aug 17, 2016 at 9:54 AM, Manjeet Singh <
>> > > manjeet.chandhok@gmail.com <javascript:;>
>> > > > <javascript:;>>
>> > > > wrote:
>> > > >
>> > > > > Hi All
>> > > > >
>> > > > > Can anyone help me about how and in which version of Hbase support
>> > > Rowkey
>> > > > > lock ?
>> > > > > I have seen article about rowkey lock but it was about .94
>> version it
>> > > > said
>> > > > > that if row key not exist and any update request come and that
>> rowkey
>> > > not
>> > > > > exist then in this case Hbase hold the lock for 60 sec.
>> > > > >
>> > > > > currently I am using Hbase 1.2.2 version
>> > > > >
>> > > > > Thanks
>> > > > > Manjeet
>> > > > >
>> > > > >
>> > > > >
>> > > > > --
>> > > > > luv all
>> > > > >
>> > > >
>> > > >
>> > > >
>> > > > --
>> > > > luv all
>> > > >
>> > >
>> > >
>> > > --
>> > > -Dima
>> > >
>> >
>> >
>> >
>> > --
>> > luv all
>> >
>>
>>
>> --
>> -Dima
>>
>
>
>
> --
> luv all
>



-- 
luv all

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