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Subject: Re: leveled compaction and tombstoned data
From: Jeremy Hanna <jeremy.hanna1234@gmail.com>
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Date: Thu, 8 Nov 2012 13:37:49 -0600
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To: user@cassandra.apache.org

LCS works well in specific circumstances, this blog post gives some good =
considerations: =
http://www.datastax.com/dev/blog/when-to-use-leveled-compaction

On Nov 8, 2012, at 1:33 PM, Aaron Turner <synfinatic@gmail.com> wrote:

> "kill performance" is relative.  Leveled Compaction basically costs 2x =
disk IO.  Look at iostat, etc and see if you have the headroom.
>=20
> There are also ways to bring up a test node and just run Level =
Compaction on that.  Wish I had a URL handy, but hopefully someone else =
can find it.
>=20
> Also, if you're not using compression, check it out.
>=20
> On Thu, Nov 8, 2012 at 11:20 AM, B. Todd Burruss <btoddb@gmail.com> =
wrote:
> we are running Datastax enterprise and cannot patch it.  how bad is
> "kill performance"?  if it is so bad, why is it an option?
>=20
>=20
> On Thu, Nov 8, 2012 at 10:17 AM, Radim Kolar <hsn@filez.com> wrote:
> > Dne 8.11.2012 19:12, B. Todd Burruss napsal(a):
> >
> >> my question is would leveled compaction help to get rid of the =
tombstoned
> >> data faster than size tiered, and therefore reduce the disk space =
usage?
> >>
> > leveled compaction will kill your performance. get patch from jira =
for
> > maximum sstable size per CF and force cassandra to make smaller =
tables, they
> > expire faster.
> >
>=20
>=20
>=20
> --=20
> Aaron Turner
> http://synfin.net/         Twitter: @synfinatic
> http://tcpreplay.synfin.net/ - Pcap editing and replay tools for Unix =
& Windows
> Those who would give up essential Liberty, to purchase a little =
temporary=20
> Safety, deserve neither Liberty nor Safety. =20
>     -- Benjamin Franklin
> "carpe diem quam minimum credula postero"
>=20