after tried nodetool -h reagon repair key cf, I found that even repair single CF, it involves rebuild all sstables(using nodetool compactionstats), is that normal?
On Thu, Jul 21, 2011 at 7:56 AM, Aaron Morton <aa...@thelastpickle.com>wrote: > If you have never run repair also check the section on repair on this page > http://wiki.apache.org/cassandra/Operations About how frequently it should > be run. > > There is an issue where repair can stream too much data, and this can lead > to excessive disk use. > > My non scientific approach to the never run repair before problem is to > repair a single CF at a time, starting with the small ones that are less > likely to have differences as they will stream the smallest amount of data. > > If you really want to conserve disk IO during the repair consider disabling > the minor compaction by setting the min and max thresholds to 0 via node > tool. > > hope that helps. > > > ----------------- > Aaron Morton > Freelance Cassandra Developer > @aaronmorton > http://www.thelastpickle.com > > On 20/07/2011, at 11:46 PM, Yan Chunlu <springri...@gmail.com> wrote: > > just found this: > <https://issues.apache.org/jira/browse/CASSANDRA-2156> > https://issues.apache.org/jira/browse/CASSANDRA-2156 > > but seems only available to 0.8 and people submitted a patch for 0.6, I am > using 0.7.4, do I need to dig into the code and make my own patch? > > does add compaction throttle solve the io problem? thanks! > > On Wed, Jul 20, 2011 at 4:44 PM, Yan Chunlu < <springri...@gmail.com> > springri...@gmail.com> wrote: > >> at the beginning of using cassandra, I have no idea that I should run >> "node repair" frequently, so basically, I have 3 nodes with RF=3 and have >> not run node repair for months, the data size is 20G. >> >> the problem is when I start running node repair now, it eat up all disk io >> and the server load became 20+ and increasing, the worst thing is, the >> entire cluster has slowed down and can not handle request. so I have to stop >> it immediately because it make my web service unavailable. >> >> the server has Intel Xeon-Lynnfield 3470-Quadcore [2.93GHz] and 8G >> memory, with Western Digital WD RE3 WD1002FBYS SATA disk. >> >> I really have no idea what to do now, as currently I have already found >> some data loss, any suggestions would be appreciated. >> > > > > -- > 闫春路 > > -- 闫春路
