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From Keith Turner <ke...@deenlo.com>
Subject Re: Reverse Index Timestamp
Date Tue, 27 Nov 2012 16:51:24 GMT
Keith

On Tue, Nov 27, 2012 at 10:41 AM, Roshan Punnoose <roshanp@gmail.com> wrote:

> I want to have a table where the row will consist of "<string>-<reverse
> index timestamp>". But this means that the data is always being prefixed to
> the beginning of the row (or tablet if the row is large). Will this be a
> problem for compaction or performance?


Can you tell me more about what <string> is?  For example is it a hash or
does it come from the set "foo1","foo2","foo3".   How does it change over
time?  I think the answer to your question depends on what <string> is.


>
> I don't know if I heard this correctly, but someone once mentioned that
> making the row id the direct timestamp could cause performance issues
> because data is always going to one tablet, but also because there is
> trouble splitting since it always appends to the tablet. Is this true, is
> it similar to what could happen if I am always prefixing to a tablet?
>

Yes using a timestamp for a row could cause data from many clients to
always go to the same tablet, which would be bad for performance on a
cluster.


>
> Thanks!
> Roshan
>

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