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 <[email protected]> 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 <[email protected] > <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 <[email protected] > <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 < > > [email protected] <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
