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From Sumit Nigam <>
Subject Re: ALTER table
Date Tue, 12 Jan 2016 08:21:51 GMT
Hi Krishna,
 I'd agree about #salt_buckets as being a multiple of #region servers. But, that may not take
into account (at least, completely) the number of region servers that we add, going forward.
Or is it not a bad idea to begin with a large number of pre-splits initially? That may impact
read speed though.

      From: Krishna <>
 To: "" <> 
 Sent: Tuesday, January 12, 2016 12:17 PM
 Subject: Re: ALTER table
General recommendation is to choose salt number as a small multiple of region servers. If
you are aware of your key distribution you can pre-split the table in phoenix too along specific
split points. 

On Monday, January 11, 2016, Ken Hampson <> wrote:

I ran into this as well just today, and am very interested in the answer. HBase itself allows
regions to be explicitly split as well as pre-split and auto-split. SALT_BUCKETS seems like
a pre-split equivalent of sorts, so I am interested to see what there may be in terms of auto-
and explicit-salting.
- Ken

On Mon, Jan 11, 2016 at 6:10 AM Sumit Nigam <> wrote:

SALT_BUCKETS cannot be altered after table creation. I'd like to know from advanced users
as to how do we ensure that salt buckets hold up as data grows? I might state salt buckets
as say, 8 when I create table and that may hold up for a long time. However, as data is increasing
those salt buckets will not be sufficient. Also, the value may not always be optimal for different
read/ write load types.
Or would specifying initial salt buckets will hold up as long as I make sure I keep adding
region servers as I go along?


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