Re: building a new email-like inbox service with cassandra

Yep, i've been looking at it almost as you were pushing it :) I'll keep looking, thanks!! -- Dotan, @jondot On Wed, Dec 7, 2011 at 3:26 AM, Rustam Aliyev wrote: > Hi, > > Just updating this thread: > > We've pushed initial version to github today. You can find sour

Re: sstable count=0, why nodetool ring is not 0

in the Cassandra wiki, I found this " ColumnFamilyStoreMBean exposes sstable space used as getLiveDiskSpaceUsed (only includes size of non-obsolete files) and getTotalDiskSpaceUsed (includes everything)." maybe this is the answer. On Wed, Dec 7, 2011 at 11:57 AM, 祝海通 wrote: > hi,all > > We are

Performance and Maintenance Question

We have a cluster with 10 server, replication-factor 2, using Cassandra 0.8.7., and . we are absolute newbies with cassandra ;-) In column family "A" we are writing 40.000 rows per second for 72 hours (no reads, only reads on column family "B"). After that we insert for one hour 10.000.000 rows

Re: sstable count=0, why nodetool ring is not 0

Hi, What kind of process did you use for loading 400GB of data? Thanks -- Dotan, @jondot On Wed, Dec 7, 2011 at 5:57 AM, 祝海通 wrote: > hi,all > > We are using Cassandra 1.0.2. I am testing the TTL with loading 400G. > When all the data are expired, I waited for some

changing cluster topology - introducing brisk dc

I have equally balanced, 36 node cluster,  RandomPartitioner, RF=3 SimpleStrategy, SimpleSnitch, cassandra 0.8.7 I'd like to change cluster topology because:  - after some reorganization in our DC 18 nodes was moved to separate room.  - I'd like to change 9 nodes to brisk to have analytical process

Re: node.js library?

On Mon, Dec 5, 2011 at 8:26 AM, Joe Stein wrote: > Hey folks, so I have been noodling on using node.js as a new front end for > the system I built for doing real time aggregate metrics within our > distributed systems. > > Does anyone have experience or background story on this > lib? http://code.

Re: Cassandra not suitable?

Where do you see the timeout exceptions? in the mappers? How many mappers reducers slots are you using? What does your disk setup look like? do you have HDFS on same disk as cassandra data dir? -Jake On Tue, Dec 6, 2011 at 4:50 AM, Patrik Modesto wrote: > Hi, > > I'm quite desperate about Cass

Re: node.js library?

Thanks Eric! On Wed, Dec 7, 2011 at 8:37 AM, Eric Evans wrote: > On Mon, Dec 5, 2011 at 8:26 AM, Joe Stein wrote: > > Hey folks, so I have been noodling on using node.js as a new front end > for > > the system I built for doing real time aggregate metrics within our > > distributed systems. > >

Re: cassandra most stable version ?

Thanks. Anyone else to share his production version and some feedbacks ? - Pierre -Original Message- From: Jahangir Mohammed Date: Tue, 6 Dec 2011 17:36:37 To: Reply-To: user@cassandra.apache.org Subject: Re: cassandra most stable version ? We are running 0.8.7. No big issues so f

AW: cassandra most stable version ?

Hi Pierre, we started some Tests with 1.0.x, and had a lot of trouble. Now we are running 0.8.7 and had also no failures and good performance. -Karsten Von: Pierre Chalamet [mailto:pie...@chalamet.net] Gesendet: Mittwoch, 7. Dezember 2011 16:37 An: user@cassandra.apache.org Betreff: Re: cassand

exporting data from Cassandra cluster

Hello everyone. 3 node Cassandra 0.8.5 cluster. I've left the system running in production environment for long term testing. I've accumulated about 350GB of data with RF=2. The machines I used for the tests are older and need to be replaced. Because of this I need to export the data to a permanen

RE: cassandra most stable version ?

Hi Pierre, Using 1.0.2 without any problem so far. 0.8.x had problems for us. Never tried 0.8.7 or later tough. Carlos Rolo From: Karsten Pappert [mailto:kars...@pappert.de] Sent: woensdag 7 december 2011 16:54 To: user@cassandra.apache.org; pie...@chalamet.net Subject: AW: cassandra most stabl

Re: Cassandra not suitable?

If you're getting lots of timeout exceptions with mapreduce, you might take a look at http://wiki.apache.org/cassandra/HadoopSupport#Troubleshooting We saw that and tweaked a variety of things - all of which are listed there. Ultimately, we also boosted hadoop's tolerance for them as well and it

RE: exporting data from Cassandra cluster

Alex, Is there a reason you don't just join new hardware to the cluster and then remove the old hardware from the cluster? That would seem like the easiest way to accomplish a hardware upgrade. Tim Smith | noc administrator O: +1 503.553.2554 M: 707.738.8132 TW: @tas50 webtrends

Cassandra strategy for data replicating

Hi ppl, I'm new on Cassandra, but I installed here a Cassandra cluster with a set of three nodes. I'm wondering if there is a strategy that allow me create keyspaces that only shares the keys to another nodes? For example, I would like to have in Cassandra a keyspace with data saved in local key

EC2 Maintenance Reboot

I just received an email from AWS about rebooting my EC2 instance for maintenance. Thankfully this is just my webhead, but I'm curious have others experienced this with a Cassandra instance? http://aws.amazon.com/maintenance-help/ The details seem to say that if you allow them to do the reboot fo

forceUserDefinedCompaction -- how to use it?

Can anyone provide an example of how to use forceUserDefinedCompaction? Thanks Maxim

Re: exporting data from Cassandra cluster

Hi Tim, There is actully...the old HW will be decommissioned before the one arrives. In the meantime I need to store my data in another place :) I've got your suggestion of how I would've done it if I didn't have this problem. Cheers, Alex On Wed, Dec 7, 2011 at 5:47 PM, Tim Smith wrote: > Al

RE: cassandra most stable version ?

0.8.7 Best regards/ Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.com Phone: +370 5 212 3063. Fax: +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania [Adform news] [Visit us!] Follow: [twitter]

Re: exporting data from Cassandra cluster

Hello Alexandru, as you probably know, my group is using Amazon S3 to permanently (or sem-permanently) park the data in CSV format, which makes it portable and we can load it into anything if needed, or analyze on its own. Just my half of a Swiss centime :) And, because the S3 option is not f

Re: exporting data from Cassandra cluster

Stop your current cluster. Start a new cassandra instance on the machine you want to store your data on. Use the sstable loader to load the sstables from all of the current machines into the new machine. Run major compaction a couple times. You will have all of the data on one machine. On

CPU bound workload

Hello, I've got a batch process running every so often that issues a bunch of counter increments. I have noticed that when this process runs without being throttled it will raise the CPU to 80-90% utilization on the nodes handling the requests. This in turns timeouts and general lag on queries runn

upgrading to 1.0.3+

I noticed this when upgrading a cluster from 1.0.1 to 1.0.5. We moved one node up to 1.0.5 to test everything was ok and a repair ran from that node. It streamed files with the new minor file version number to nodes that were 1.0.1 On restarting one of the nodes while still at 1.0.1 we got th

Atomic Operations in Cassandra

Hi All, I'm using Cassandra 1.0.3 (with Hector 0.7). What is the granularity of atomic read and write operations with Cassandra. I.e. is the insert or update of an individual column an atomic operation (in the sense that it either fails or persists completely), or is the insert or update of an ent

Mixing Columns with SuperColoumns within the same Row

Hi All, I'm using Cassandra 1.0.3. Can I have (simple) Columns and SuperColumns within the same row of a SuperColumnFamily? Cheers and thanks for any kind help! Chris

Re: Repair failure under 0.8.6

I'm still having tons of problems with repairs and compactions, where the nodes are declared dead in their log files, although they were online at all times. This leads to problem behavior, i.e. once again I see that repair fails, and the cluster becomes unusable since there is no space to com

Re: sstable count=0, why nodetool ring is not 0

We are testing the the performance of Cassandra for Big Data. Now I also have the problem. From nodetool cfstats, the space used (live) is 7 times than the Space used (total). Why? thx On Wed, Dec 7, 2011 at 5:58 PM, Dotan N. wrote: > Hi, > What kind of process did you use for loading 400GB of

Re: sstable count=0, why nodetool ring is not 0

I count the disk usage. I found that from nodetool information, space used (live) is about the nodetool ring info. space used(total) is about the disk usage. thx On Thu, Dec 8, 2011 at 9:53 AM, 祝海通 wrote: > > We are testing the the performance of Cassandra for Big Data. Now I also > have the p

Cassandra behavior too fragile?

OK, thanks to the excellent help of Datastax folks, some of the more severe inconsistencies in my Cassandra cluster were fixed (after a node was down and compactions failed etc). I'm still having problems as reported in "repairs 0.8.6." thread. Thing is, why is it so easy for the repair proces

Re: Cassandra behavior too fragile?

> Thing is, why is it so easy for the repair process to break? OK, I admit I'm > not sure why nodes are reported as "dead" once in a while, but it's > absolutely certain that they simply don't fall off the edge, are knocked out > for 10 min or anything like that. Why is there no built-in tolerance/

Composite columns vs Protocol Buffers when all you need is to pack many things in a single column

I know Composite columns are used for some very useful scenarios(like to replace super columns) which cannot be helped with anything else. But, for situations when you just need to pack many things in a single column efficiently and such that the retrievals are also performant, which one should be

Re: Mixing Columns with SuperColoumns within the same Row

On Wed, Dec 7, 2011 at 3:59 PM, Christof Bornhoevd wrote: > Hi All, > > I'm using Cassandra 1.0.3. Can I have (simple) Columns and SuperColumns > within the same row of a SuperColumnFamily? Nope. Personally, i avoid super columns all together. -- Aaron Turner http://synfin.net/         Twitte

Schematool

Hi, Since schematool has been removed from Cassandra is there a way to extract the schema from a working cluster in order to create a new empty cluster? Thanks Michael

Re: Cassandra not suitable?

Thank you Jeremy, I've already changed the max.*.failures to 20, it help jobs to finish but doesn't solve the source of the timeouts. I'll try the other tips. Regards, Patrik On Wed, Dec 7, 2011 at 17:29, Jeremy Hanna wrote: > If you're getting lots of timeout exceptions with mapreduce, you migh

Re: Cassandra not suitable?

Hi Jake, I see the timeouts in mappers as well as at random-access backend daemons (for web services). There are now 10 mappers, 2 reducers on each node. There is one big 4-disk raid10 array on each node on which there is cassandra together with HDFS. We store just few GB of files on HDFS, otherwi

Re: Upgrade from 0.6 to 1.0

I did this just last week, 0.6.13 -> 1.0.5. Basically, I grabbed the 0.7 distribution and ran the configuration conversion tool there first, but since the config it produced wasn't compatible with 1.0, in the end I just opened two editor windows, one with my 0.6 config and one with the 1.0 cas