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Date: Fri, 15 Apr 2011 16:19:50 +0200
Message-ID: <BANLkTi=2uuM-qnzUnD=imbEQnNubkK0sxw@mail.gmail.com>
Subject: Re: How to warm up a cold node
From: Peter Schuller <peter.schuller@infidyne.com>
To: user@cassandra.apache.org
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> Hi everyone, is there any recommended procedure to warm up a node before
> bringing it up?

Currently the only out-of-the-box support for warming up caches is
that implied by the key cache and row cache, which will pre-heat on
start-up. Indexes will be indirectly preheated by index sampling, to
the extent that they operating system retains them in page cache.

If you're wanting to pre-heat sstables there's currently no way to do
that (but it's a useful feature to have). Pragmatically, you can
script something that e.g. does "cat path/to/keyspace/* > /dev/null"
or similar. But that only works if the total database size fits
reasonably well in page cache.

Pre-heating sstables on a per-cf basis on start-up would be a nice
feature to have.

-- 
/ Peter Schuller