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From Jonathan Ellis <jbel...@gmail.com>
Subject Re: Range scan performance in 0.6.0 beta2
Date Fri, 26 Mar 2010 12:47:10 GMT
On Fri, Mar 26, 2010 at 7:40 AM, Henrik Schröder <skrolle@gmail.com> wrote:
> For each indexvalue we insert a row where the key is indexid + ":" +
> indexvalue encoded as hex string, and the row contains only one column,
> where the name is the object key encoded as a bytearray, and the value is
> empty.

It's a unique index then?  And you're trying to read things ordered by
the index, not just "give me keys with that have a column with this
value?"

> These numbers are slightly better than our previous OPP tries, but nothing
> significant. For what it's worth, if we're only doing writes, the machine
> bottlenecks on disk I/O as expected, but whenever we do reads, it
> bottlenecks on CPU usage instead. Is this expected?

Yes.

> Also, how would dynamic column families help us?

You don't have to mess with key prefixes, since each CF contains only
one type of index.

-Jonathan

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