Hello, I just stated that if you use QUORUM or in fact using ALL, since you're running ONE, this is a non-issue.
Regarding incremental repairs you can read here: http://thelastpickle.com/blog/2017/12/14/should-you-use-incremental-repair.html You can't run repair -pr simultaneously. You can try to use a tool like Reaper to better manage and schedule repairs, but I doubt it will speed up a lot. Regards, Carlos Juzarte Rolo Cassandra Consultant / Datastax Certified Architect / Cassandra MVP Pythian - Love your data rolo@pythian | Twitter: @cjrolo | Skype: cjr2k3 | Linkedin: *linkedin.com/in/carlosjuzarterolo <http://linkedin.com/in/carlosjuzarterolo>* Mobile: +351 918 918 100 www.pythian.com On Sun, Apr 22, 2018 at 11:39 AM, Nuno Cervaens - Hoist Group - Portugal < nuno.cerva...@hoistgroup.com> wrote: > Hi Carlos, > > > Thanks for the reply. > > Isnt the consistency level defined per session? All my session, being for > read or write as defaulted to ONE. > > > Movid to SSD is for sure an obvious improvement but not possible at the > moment. > > My goal is to really spend the lowest time possible on running a repair > throughout all the nodes. > > Are there any more downsides to run nodetool repair -pr simultaneously on > each node, besides the cpu and mem overload? > > Also if someone can clarify about the safety of an incremental repair. > > > thanks, > > nuno > ------------------------------ > *From:* Carlos Rolo <r...@pythian.com> > *Sent:* Friday, April 20, 2018 4:55:21 PM > *To:* firstname.lastname@example.org > *Subject:* Re: cassandra repair takes ages > > Changing the datadrives to SSD would help to speed up the repairs. > > Also don't run 3 node, RF2. That makes Quorum = All. > > Regards, > > Carlos Juzarte Rolo > Cassandra Consultant / Datastax Certified Architect / Cassandra MVP > > Pythian - Love your data > > rolo@pythian | Twitter: @cjrolo | Skype: cjr2k3 | Linkedin: > *linkedin.com/in/carlosjuzarterolo > <http://linkedin.com/in/carlosjuzarterolo>* > Mobile: +351 918 918 100 > www.pythian.com > > On Fri, Apr 20, 2018 at 4:42 PM, Nuno Cervaens - Hoist Group - Portugal < > nuno.cerva...@hoistgroup.com> wrote: > > Hello, > > I have a 3 node cluster with RF 2 and using STCS. I use SSDs for > commitlogs and HDDs for data. Apache Cassandra version is 3.11.2. > I basically have a huge keyspace ('newts' from opennms) and a big keyspace > ('opspanel'). Here's a summary of the 'du' output for one node (which is > more or less the same for each node): > > 51G ./data/opspanel > 776G ./data/newts/samples-00ae9420ea0711e5a39bbd7839a19930 > 776G ./data/newts > > My issue is that running a 'nodetool repair -pr' takes one day an a half > per node and as I want to store daily snapshots (for the past 7 days), I > dont see how I can do this as repairs take too long. > For example I see huge compactions and validations that take lots of hours > (compactionstats taken at different times): > > id compaction type keyspace > table completed total unit progress > 7125eb20-446b-11e8-a57d-f36e88375e31 Compaction newts samples > 294177987449 835153786347 bytes 35,22% > > id compaction type keyspace > table completed total unit progress > 6aa5ce51-4425-11e8-a7c1-572dede7e4d6 Anticompaction after repair > newts samples 581839334815 599408876344 bytes 97,07% > > id compaction type keyspace > table completed total unit progress > 69976700-43e2-11e8-a7c1-572dede7e4d6 Validation newts samples > 63249761990 826302170493 bytes 7,65% > 69973ff0-43e2-11e8-a7c1-572dede7e4d6 Validation newts samples > 102513762816 826302170600 bytes 12,41% > > Is there something I can do to improve the situation? > > Also, is an incremental repair (apparently nodetool's default) safe? As I > see in the datastax documentation that the incremental should not be used, > only the full. Can you please clarify? > > Thanks for the feedback. > Nuno > > > > -- > > > > -- --