Re: Java Client Driver for Cassandra 2.0.14

2015-05-15 Thread Artur Kronenberg
I started using the datastax driver (coming from astynax driver) recently. It is awesome! Use it :D https://github.com/datastax/java-driver Cheers, artur On 15/05/15 10:32, Rohit Naik wrote: DISCLAIMER == This e-mail may contain privileged an

Nodetool removenode stuck

2015-01-19 Thread Artur Kronenberg
Hi, we have had an issue with one of our nodes today: 1. Due to a wrong setup the starting node failed to properly bootstrap. It was shown as UN in the cluster however did not contain any data and we shut it down to fix our configuration issue. 2. We figured we need to remove the node from

Re: How to prevent the removed DC comes back automactically?

2014-08-14 Thread Artur Kronenberg
Hey, not sure if that's what you're looking for but you can use auto_bootstrap=false in your yaml file to prevent nodes from bootstrapping themselves on startup. This option has been removed and the default is true. You can add it to your configuration though. There's a bit of documentation

Re: Configuring all nodes as seeds

2014-06-18 Thread Artur Kronenberg
Hi, pretty sure we started out like that and had not seen any problems doing that. On a side node, that config may become inconsistent anyway after adding new nodes, because I think you'll need a restart of all your nodes if you add new seeds to the yaml file. (Though that's just assumption)

Re: repair -pr does not return

2014-05-02 Thread Artur Kronenberg
Hi, to be honest 2 days for 200GB nodes doesn't sound too unreasonable to me (depending on your hardware of course). We were running a ~20 GB cluster with regualr hard drives (no SSD) and our first repair ran a day as well if I recall correctly. We since improved our hardware and got it down

Backup procedure

2014-05-02 Thread Artur Kronenberg
Hi, we are running a 7 node cluster with an RF of 5. Each node holds about 70% of the data and we are now wondering about the backup process. 1. Is there a best practice procedure or a tool that we can use to have one backup that holds 100 % of the data or is it necessary for us to take

Re: How to extract information from commit log?

2014-03-19 Thread Artur Kronenberg
Hi, we did something similar. We did utilize some cassandra code though and wrote a custom commitlog reader that outputs our data into a readable form. You can look here:

Re: Question about node tool repair

2014-01-22 Thread Artur Kronenberg
About repairs, we encountered a similar problem with our setup where repairs would take ages to complete. Based on your setup you can try loading data into page cache before running repairs. Depending on how much data you can hold in cache, this will speed up your repairs massively. --

Re: Try to configure commitlog_archiving.properties

2013-12-13 Thread Artur Kronenberg
It's been a while since I tried that but here are some things I can think of: * the .log.out seems wrong. Unless your cassandra commitlogs don't end in .log.out. I tried this locally with your script and my commitlogs get extracted to .log files for me. * I never tried the restore procedure

Re: Try to configure commitlog_archiving.properties

2013-12-11 Thread Artur Kronenberg
hi Bonnet, that doesn't seem to be a problem with your archiving, rather with the restoring. What is your restore command? -- artur On 11/12/13 13:47, Bonnet Jonathan. wrote: Bonnet Jonathan jonathan.bonnet at externe.bnpparibas.com writes: Thanks a lot, It Works, i see commit log

Re: Try to configure commitlog_archiving.properties

2013-12-11 Thread Artur Kronenberg
, artur On 11/12/13 14:09, Bonnet Jonathan. wrote: Artur Kronenberg artur.kronenberg at openmarket.com writes: hi Bonnet, that doesn't seem to be a problem with your archiving, rather with the restoring. What is your restore command? -- artur On 11/12/13 13:47

Re: Try to configure commitlog_archiving.properties

2013-12-10 Thread Artur Kronenberg
Hi, There is some docs on the internet for this operations. It is basically as presented in the archive-commitlog file. (commitlog_archiving.properties). The way the operations work: The operation is called automatically with parameters that give you control over what you want to do with

Re: reads and compression

2013-11-29 Thread Artur Kronenberg
Hi John, I am trying again :) The way I understand it is that compression gives you the advantage of having to use way less IO and rather use CPU. The bottleneck of reads is usually the IO time you need to read the data from disk. As a figure, we had about 25 reads/s reading from disk, while

Re: Nodetool cleanup

2013-11-25 Thread Artur Kronenberg
Hi Julien, I hope I get this right :) a repair will trigger a mayor compaction on your node which will take up a lot of CPU and IO performance. It needs to do this to build up the data structure that is used for the repair. After the compaction this is streamed to the different nodes in

Re: Sorting keys for batch reads to minimize seeks

2013-10-22 Thread Artur Kronenberg
...@adform.com wrote: Read latency depends on many factors, don't forget physics. If it meets your requirements, it is good. -Original Message- From: Artur Kronenberg [mailto:artur.kronenb...@openmarket.com mailto:artur.kronenb...@openmarket.com] Sent: Friday, October 18, 2013 1:03

Re: Sorting keys for batch reads to minimize seeks

2013-10-18 Thread Artur Kronenberg
this message in error, please contact the sender immediately and irrevocably delete this message and any copies.-Original Message- From: Artur Kronenberg [mailto:artur.kronenb...@openmarket.com] Sent: Thursday, October 17, 2013 7:40 PM To: user@cassandra.apache.org Subject: Sorting keys for batch

Sorting keys for batch reads to minimize seeks

2013-10-17 Thread Artur Kronenberg
Hi, I am looking to somehow increase read performance on cassandra. We are still playing with configurations but I was thinking if there would be solutions in software that might help us speed up our read performance. E.g. one idea, not sure how sane that is, was to sort read-batches by

Heap requirement for Off-heap space

2013-10-11 Thread Artur Kronenberg
Hi, I was playing around with cassandra off-heap options. I configured 3 GB off-heap for my row cache and 2 GB Heap space for cassandra. After running a bunch of load tests against it I saw the cache warm up. Doing a jmap histogram I noticed a lot of offHeapkey objects. At that point my row

Rowcache and quorum reads cassandra

2013-10-10 Thread Artur Kronenberg
I was reading through configuration tips for cassandra and decided to use row-cache in order to optimize the read performance on my cluster. I have a cluster of 10 nodes, each of them opeartion with 3 GB off-heap using cassandra 2.4.1. I am doing local quorum reads, which means that I will

Re: Rowcache and quorum reads cassandra

2013-10-10 Thread Artur Kronenberg
/ On Thu, Oct 10, 2013 at 6:40 AM, Artur Kronenberg artur.kronenb...@openmarket.com mailto:artur.kronenb...@openmarket.com wrote: I was reading through configuration tips for cassandra and decided to use row-cache in order to optimize the read performance on my cluster. I have