On Sat, Apr 14, 2012 at 1:57 PM, Igor <i...@4friends.od.ua> wrote: > Hi! > > What is the difference between 'repair' and '-pr repair'? Simple repair > touch all token ranges (for all nodes) and -pr touch only range for which > given node responsible? > > -pr only touches the primary range of the node. If you executes -pr against all nodes in replica groups, then all ranges are repaired.
> > > On 04/12/2012 05:59 PM, Sylvain Lebresne wrote: > >> On Thu, Apr 12, 2012 at 4:06 PM, Frank Ng<buzzt...@gmail.com> wrote: >> >>> I also noticed that if I use the -pr option, the repair process went down >>> from 30 hours to 9 hours. Is the -pr option safe to use if I want to run >>> repair processes in parallel on nodes that are not replication peers? >>> >> There is pretty much two use case for repair: >> 1) to rebuild a node: if say a node has lost some data due to a hard >> drive corruption or the like and you want to to rebuild what's missing >> 2) the periodic repairs to avoid problem with deleted data coming back >> from the dead (basically: >> http://wiki.apache.org/**cassandra/Operations#** >> Frequency_of_nodetool_repair<http://wiki.apache.org/cassandra/Operations#Frequency_of_nodetool_repair> >> ) >> >> In case 1) you want to run 'nodetool repair' (without -pr) against the >> node to rebuild. >> In case 2) (which I suspect is the case your talking now), you *want* >> to use 'nodetool repair -pr' on *every* node of the cluster. I.e. >> that's the most efficient way to do it. The only reason not to use -pr >> in this case would be that it's not available because you're using an >> old version of Cassandra. And yes, it's is safe to run with -pr in >> parallel on nodes that are not replication peers. >> >> -- >> Sylvain >> >> >> thanks >>> >>> >>> On Thu, Apr 12, 2012 at 12:06 AM, Frank Ng<berryt...@gmail.com> wrote: >>> >>>> Thank you for confirming that the per node data size is most likely >>>> causing the long repair process. I have tried a repair on smaller >>>> column >>>> families and it was significantly faster. >>>> >>>> On Wed, Apr 11, 2012 at 9:55 PM, aaron morton<aa...@thelastpickle.com** >>>> > >>>> wrote: >>>> >>>>> If you have 1TB of data it will take a long time to repair. Every bit >>>>> of >>>>> data has to be read and a hash generated. This is one of the reasons we >>>>> often suggest that around 300 to 400Gb per node is a good load in the >>>>> general case. >>>>> >>>>> Look at nodetool compactionstats .Is there a validation compaction >>>>> running ? If so it is still building the merkle hash tree. >>>>> >>>>> Look at nodetool netstats . Is it streaming data ? If so all hash trees >>>>> have been calculated. >>>>> >>>>> Cheers >>>>> >>>>> >>>>> ----------------- >>>>> Aaron Morton >>>>> Freelance Developer >>>>> @aaronmorton >>>>> http://www.thelastpickle.com >>>>> >>>>> On 12/04/2012, at 2:16 AM, Frank Ng wrote: >>>>> >>>>> Can you expand further on your issue? Were you using Random Patitioner? >>>>> >>>>> thanks >>>>> >>>>> On Tue, Apr 10, 2012 at 5:35 PM, David Leimbach<leim...@gmail.com> >>>>> wrote: >>>>> >>>>>> I had this happen when I had really poorly generated tokens for the >>>>>> ring. Cassandra seems to accept numbers that are too big. You get >>>>>> hot >>>>>> spots when you think you should be balanced and repair never ends (I >>>>>> think >>>>>> there is a 48 hour timeout). >>>>>> >>>>>> >>>>>> On Tuesday, April 10, 2012, Frank Ng wrote: >>>>>> >>>>>>> I am not using tier-sized compaction. >>>>>>> >>>>>>> >>>>>>> On Tue, Apr 10, 2012 at 12:56 PM, Jonathan Rhone<rh...@tinyco.com> >>>>>>> wrote: >>>>>>> >>>>>>>> Data size, number of nodes, RF? >>>>>>>> >>>>>>>> Are you using size-tiered compaction on any of the column families >>>>>>>> that hold a lot of your data? >>>>>>>> >>>>>>>> Do your cassandra logs say you are streaming a lot of ranges? >>>>>>>> zgrep -E "(Performing streaming repair|out of sync)" >>>>>>>> >>>>>>>> >>>>>>>> On Tue, Apr 10, 2012 at 9:45 AM, Igor<i...@4friends.od.ua> wrote: >>>>>>>> >>>>>>>>> On 04/10/2012 07:16 PM, Frank Ng wrote: >>>>>>>>> >>>>>>>>> Short answer - yes. >>>>>>>>> But you are asking wrong question. >>>>>>>>> >>>>>>>>> >>>>>>>>> I think both processes are taking a while. When it starts up, >>>>>>>>> netstats and compactionstats show nothing. Anyone out there >>>>>>>>> successfully >>>>>>>>> using ext3 and their repair processes are faster than this? >>>>>>>>> >>>>>>>>> On Tue, Apr 10, 2012 at 10:42 AM, Igor<i...@4friends.od.ua> >>>>>>>>> wrote: >>>>>>>>> >>>>>>>>>> Hi >>>>>>>>>> >>>>>>>>>> You can check with nodetool which part of repair process is slow >>>>>>>>>> - >>>>>>>>>> network streams or verify compactions. use nodetool netstats or >>>>>>>>>> compactionstats. >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> On 04/10/2012 05:16 PM, Frank Ng wrote: >>>>>>>>>> >>>>>>>>>>> Hello, >>>>>>>>>>> >>>>>>>>>>> I am on Cassandra 1.0.7. My repair processes are taking over 30 >>>>>>>>>>> hours to complete. Is it normal for the repair process to take >>>>>>>>>>> this long? >>>>>>>>>>> I wonder if it's because I am using the ext3 file system. >>>>>>>>>>> >>>>>>>>>>> thanks >>>>>>>>>>> >>>>>>>>>> >>>>>>>>>> >>>>>>>>> >>>>>>>> >>>>>>>> -- >>>>>>>> Jonathan Rhone >>>>>>>> Software Engineer >>>>>>>> >>>>>>>> TinyCo >>>>>>>> 800 Market St., Fl 6 >>>>>>>> San Francisco, CA 94102 >>>>>>>> www.tinyco.com >>>>>>>> >>>>>>>> >>>>> >
