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From Martin McGovern <>
Subject Question on pending tasks in compaction manager
Date Fri, 29 Jun 2012 09:27:48 GMT
Hi All,

Could someone explain why the compaction manager stops compacting when it
has a number of pending tasks?

I have a test cluster that I am using to stress test IO throughput, i.e.
find out what a safe load for our hardware is. Over a 16 hour period my
node cluster completes approximately 49,000 tasks per node. After stopping
my test compaction continues for a few minutes then stops. There are ~7,000
tasks still pending. No more tasks will be executed until I start another
test and the 7000 pending will never be executed.

I'm using leveled compaction with 5MB SS tables and my tests have a 50:50
read:write ratio. Each value is a 10K byte array with random content.


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