Hi, To summarize who we have heard from so far
WRT to changing just the default: +1: Jon Haddadd Ben Bromhead Alain Rodriguez Sankalp Kohli (not explicit) -0: Sylvaine Lebresne Jeff Jirsa Not sure: Kurt Greaves Joshua Mckenzie Benedict Elliot Smith WRT to change the representation: +1: There are only conditional +1s at this point -0: Sylvaine Lebresne -.5: Jeff Jirsa This (https://github.com/aweisberg/cassandra/commit/a9ae85daa3ede092b9a1cf84879fb1a9f25b9dce) is a rough cut of the change for the representation. It needs better naming, unit tests, javadoc etc. but it does implement the change. Ariel On Fri, Oct 19, 2018, at 3:42 PM, Jonathan Haddad wrote: > Sorry, to be clear - I'm +1 on changing the configuration default, but I > think changing the compression in memory representations warrants further > discussion and investigation before making a case for or against it yet. > An optimization that reduces in memory cost by over 50% sounds pretty good > and we never were really explicit that those sort of optimizations would be > excluded after our feature freeze. I don't think they should necessarily > be excluded at this time, but it depends on the size and risk of the patch. > > On Sat, Oct 20, 2018 at 8:38 AM Jonathan Haddad <j...@jonhaddad.com> wrote: > > > I think we should try to do the right thing for the most people that we > > can. The number of folks impacted by 64KB is huge. I've worked on a lot > > of clusters created by a lot of different teams, going from brand new to > > pretty damn knowledgeable. I can't think of a single time over the last 2 > > years that I've seen a cluster use non-default settings for compression. > > With only a handful of exceptions, I've lowered the chunk size considerably > > (usually to 4 or 8K) and the impact has always been very noticeable, > > frequently resulting in hardware reduction and cost savings. Of all the > > poorly chosen defaults we have, this is one of the biggest offenders that I > > see. There's a good reason ScyllaDB claims they're so much faster than > > Cassandra - we ship a DB that performs poorly for 90+% of teams because we > > ship for a specific use case, not a general one (time series on memory > > constrained boxes being the specific use case) > > > > This doesn't impact existing tables, just new ones. More and more teams > > are using Cassandra as a general purpose database, we should acknowledge > > that adjusting our defaults accordingly. Yes, we use a little bit more > > memory on new tables if we just change this setting, and what we get out of > > it is a massive performance win. > > > > I'm +1 on the change as well. > > > > > > > > On Sat, Oct 20, 2018 at 4:21 AM Sankalp Kohli <kohlisank...@gmail.com> > > wrote: > > > >> (We should definitely harden the definition for freeze in a separate > >> thread) > >> > >> My thinking is that this is the best time to do this change as we have > >> not even cut alpha or beta. All the people involved in the test will > >> definitely be testing it again when we have these releases. > >> > >> > On Oct 19, 2018, at 8:00 AM, Michael Shuler <mich...@pbandjelly.org> > >> wrote: > >> > > >> >> On 10/19/18 9:16 AM, Joshua McKenzie wrote: > >> >> > >> >> At the risk of hijacking this thread, when are we going to transition > >> from > >> >> "no new features, change whatever else you want including refactoring > >> and > >> >> changing years-old defaults" to "ok, we think we have something that's > >> >> stable, time to start testing"? > >> > > >> > Creating a cassandra-4.0 branch would allow trunk to, for instance, get > >> > a default config value change commit and get more testing. We might > >> > forget again, from what I understand of Benedict's last comment :) > >> > > >> > -- > >> > Michael > >> > > >> > --------------------------------------------------------------------- > >> > To unsubscribe, e-mail: dev-unsubscr...@cassandra.apache.org > >> > For additional commands, e-mail: dev-h...@cassandra.apache.org > >> > > >> > >> --------------------------------------------------------------------- > >> To unsubscribe, e-mail: dev-unsubscr...@cassandra.apache.org > >> For additional commands, e-mail: dev-h...@cassandra.apache.org > >> > >> > > > > -- > > Jon Haddad > > http://www.rustyrazorblade.com > > twitter: rustyrazorblade > > > > > -- > Jon Haddad > http://www.rustyrazorblade.com > twitter: rustyrazorblade --------------------------------------------------------------------- To unsubscribe, e-mail: dev-unsubscr...@cassandra.apache.org For additional commands, e-mail: dev-h...@cassandra.apache.org
