> Is there anything to do before that? like drain or flush? For a clean shutdown I do
nodetool -h localhost disablethrift nodetool -h localhost disablegossip && sleep 10 nodetool -h localhost drain then kill > Would you recommend that? If I do it, how often should I do a full snapshot, > and how often should I backup the backup directory? Sounds like you could use Priam and be happier... http://techblog.netflix.com/2012/02/announcing-priam.html > I just saw that there is an option global_snapshot, is it still supported? I cannot find it. Try Piram or the instructions here, which are pretty much what you have described http://www.datastax.com/docs/1.0/operations/backup_restore Cheers ----------------- Aaron Morton Freelance Developer @aaronmorton http://www.thelastpickle.com On 15/08/2012, at 4:57 PM, Tamar Fraenkel <ta...@tok-media.com> wrote: > Aaron, > Thank you very much. I will do as you suggested. > > One last question regarding restart: > I assume, I should do it node by node. > Is there anything to do before that? like drain or flush? > > I am also considering enabling incremental backups on my cluster. Currently I > take a daily full snapshot of the cluster, tar it and load it to S3 (size now > is 3.1GB). Would you recommend that? If I do it, how often should I do a full > snapshot, and how often should I backup the backup directory? > > Another snapshot related question, currently I snapshot on each node and use > parallel-slurp to copy the snapshot to one node where I tar them. I just saw > that there is an option global_snapshot, is it still supported? Does that > mean that if I run it on one node the snapshot will contain data from all > cluster? How does it work in restore? Is it better than my current backup > system? > > Tamar Fraenkel > Senior Software Engineer, TOK Media > > > > ta...@tok-media.com > Tel: +972 2 6409736 > Mob: +972 54 8356490 > Fax: +972 2 5612956 > > > > > > On Tue, Aug 14, 2012 at 11:51 PM, aaron morton <aa...@thelastpickle.com> > wrote: >> According to cfstats there are the some CF with high Comacted row maximum >> sizes (1131752, 4866323 and 25109160). Others max sizes are < 1000000. Are >> these considered to be problematic, what can I do to solve that? > They are only 1, 4 and 25 MB. Not too big. > >> What should be the values of in_memory_compaction_limit_in_mb and >> concurrent_compactors and how do I change them? > Sounds like you dont have very big CF's, so changing the > in_memory_compaction_limit_in_mb may not make too much difference. > > Try changing concurrent_compactors to 2 in the yaml file. This change will > let you know if GC and compaction are related. > >> change yaml file and restart, > yes > >> What do I do about the long rows? What value is considered too big. > They churn more memory during compaction. If you have a lot of rows +32 MB I > would think about it, does not look that way. > > Cheers > > > ----------------- > Aaron Morton > Freelance Developer > @aaronmorton > http://www.thelastpickle.com > > On 15/08/2012, at 3:15 AM, Tamar Fraenkel <ta...@tok-media.com> wrote: > >> Hi! >> It helps, but before I do more actions I want to give you some more info, >> and ask some questions: >> >> Related Info >> According to my yaml file (where do I see these parameters in the jmx? I >> couldn't find them): >> in_memory_compaction_limit_in_mb: 64 >> concurrent_compactors: 1, but it is commented out, so I guess it is the >> default value >> multithreaded_compaction: false >> compaction_throughput_mb_per_sec: 16 >> compaction_preheat_key_cache: true >> According to cfstats there are the some CF with high Comacted row maximum >> sizes (1131752, 4866323 and 25109160). Others max sizes are < 1000000. Are >> these considered to be problematic, what can I do to solve that? >> During compactions Cassandra is slower >> Running Cassandra Version 1.0.8 >> Questions >> What should be the values of in_memory_compaction_limit_in_mb and >> concurrent_compactors and how do I change them? change yaml file and >> restart, or can it be done using jmx without restarting Cassandra? >> What do I do about the long rows? What value is considered too big. >> >> I appreciate your help! >> Thanks, >> >> >> >> Tamar Fraenkel >> Senior Software Engineer, TOK Media >> >> <tokLogo.png> >> >> ta...@tok-media.com >> Tel: +972 2 6409736 >> Mob: +972 54 8356490 >> Fax: +972 2 5612956 >> >> >> >> >> >> On Tue, Aug 14, 2012 at 1:22 PM, aaron morton <aa...@thelastpickle.com> >> wrote: >> There are a couple of steps you can take if compaction is causing GC. >> >> - if you have a lot of wide rows consider reducing the >> in_memory_compaction_limit_in_mb yaml setting. This will slow down >> compaction but will reduce the memory usage. >> >> - reduce concurrent_compactors >> >> Both of these may slow down compaction. Once you have GC under control you >> may want to play with memory settings. >> >> Hope that helps. >> ----------------- >> Aaron Morton >> Freelance Developer >> @aaronmorton >> http://www.thelastpickle.com >> >> On 14/08/2012, at 4:45 PM, Tamar Fraenkel <ta...@tok-media.com> wrote: >> >>> Hi! >>> I have 3 nodes ring running on Amazon EC2. >>> About once a week I see in the logs compaction messages and around the same >>> time info messages about GC (see below) that I think means it is taking too >>> long and happening too often. >>> >>> Does it mean I have to reduce my cache size? >>> Thanks, >>> Tamar >>> >>> INFO [ScheduledTasks:1] 2012-08-13 12:50:57,593 GCInspector.java (line >>> 122) GC for ParNew: 242 ms for 1 collections, 1541590352 used; max is >>> 1937768448 >>> INFO [ScheduledTasks:1] 2012-08-13 12:51:27,740 GCInspector.java (line >>> 122) GC for ParNew: 291 ms for 1 collections, 1458227032 used; max is >>> 1937768448 >>> INFO [ScheduledTasks:1] 2012-08-13 12:51:29,741 GCInspector.java (line >>> 122) GC for ParNew: 261 ms for 1 collections, 1228861368 used; max is >>> 1937768448 >>> INFO [ScheduledTasks:1] 2012-08-13 12:51:30,833 GCInspector.java (line >>> 122) GC for ParNew: 319 ms for 1 collections, 1120131360 used; max is >>> 1937768448 >>> INFO [ScheduledTasks:1] 2012-08-13 12:51:32,863 GCInspector.java (line >>> 122) GC for ParNew: 241 ms for 1 collections, 983144216 used; max is >>> 1937768448 >>> INFO [ScheduledTasks:1] 2012-08-13 12:51:33,864 GCInspector.java (line >>> 122) GC for ParNew: 215 ms for 1 collections, 967702720 used; max is >>> 1937768448 >>> INFO [ScheduledTasks:1] 2012-08-13 12:51:34,964 GCInspector.java (line >>> 122) GC for ParNew: 248 ms for 1 collections, 973803344 used; max is >>> 1937768448 >>> INFO [ScheduledTasks:1] 2012-08-13 12:51:41,211 GCInspector.java (line >>> 122) GC for ParNew: 265 ms for 1 collections, 1071933560 used; max is >>> 1937768448 >>> INFO [ScheduledTasks:1] 2012-08-13 12:51:43,212 GCInspector.java (line >>> 122) GC for ParNew: 326 ms for 1 collections, 1217367792 used; max is >>> 1937768448 >>> INFO [ScheduledTasks:1] 2012-08-13 12:51:44,212 GCInspector.java (line >>> 122) GC for ParNew: 245 ms for 1 collections, 1203481536 used; max is >>> 1937768448 >>> INFO [ScheduledTasks:1] 2012-08-13 12:51:45,213 GCInspector.java (line >>> 122) GC for ParNew: 209 ms for 1 collections, 1208819416 used; max is >>> 1937768448 >>> INFO [ScheduledTasks:1] 2012-08-13 12:51:46,237 GCInspector.java (line >>> 122) GC for ParNew: 248 ms for 1 collections, 1338361648 used; max is >>> 1937768448 >>> >>> >>> Tamar Fraenkel >>> Senior Software Engineer, TOK Media >>> >>> <tokLogo.png> >>> >>> >>> ta...@tok-media.com >>> Tel: +972 2 6409736 >>> Mob: +972 54 8356490 >>> Fax: +972 2 5612956 >>> >>> >>> >> >> > >
