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Subject: Cassandra freezes
From: Joel Samuelsson <samuelsson.joel@gmail.com>
To: user@cassandra.apache.org
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Hello,

I've been trying to load test a one node cassandra cluster. When I add lots
of data, the Cassandra node freezes for 4-5 minutes during which neither
reads nor writes are served.
During this time, Cassandra takes 100% of a single CPU core.
My initial thought was that this was Cassandra flushing memtables to the
disk, however, the disk i/o is very low during this time.
Any idea what my problem could be?
I'm running in a virtual environment in which I have no control of drives.
So commit log and data directory is (probably) on the same drive.

Best regards,
Joel Samuelsson

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<div dir="ltr">Hello,<div><br></div><div style>I&#39;ve been trying to load test a one node cassandra cluster. When I add lots of data, the Cassandra node freezes for 4-5 minutes during which neither reads nor writes are served.</div>
<div style>During this time, Cassandra takes 100% of a single CPU core.</div><div style>My initial thought was that this was Cassandra flushing memtables to the disk, however, the disk i/o is very low during this time.</div>
<div style>Any idea what my problem could be?</div><div style>I&#39;m running in a virtual environment in which I have no control of drives. So commit log and data directory is (probably) on the same drive.</div><div style>
<br></div><div style>Best regards,</div><div style>Joel Samuelsson</div></div>

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