RE: Force data to a specific node
Hi Everton, AFAIK, the pb is not forcing data to a specific node, but forcing some kind of data locality. There is things into cql to do it: you define a composite key (K1, K2), and K1 part is used as a rowkey and K2 is used within column name. So, all rows with same K1 are on the same node. See also https://issues.apache.org/jira/browse/CASSANDRA-5054 Dominique De : Everton Lima [mailto:peitin.inu...@gmail.com] Envoyé : mercredi 2 janvier 2013 19:20 À : user@cassandra.apache.org Objet : Re: Force data to a specific node We need to do this to minimize the network I/O. We have our own load data balance algorithm. We have some data that is best to process in a local machine. Is it possible? How? 2013/1/2 Edward Sargisson edward.sargis...@globalrelay.netmailto:edward.sargis...@globalrelay.net Why would you want to? From: Everton Lima peitin.inu...@gmail.commailto:peitin.inu...@gmail.com To: Cassandra-User user@cassandra.apache.orgmailto:user@cassandra.apache.org Sent: Wed Jan 02 18:03:49 2013 Subject: Force data to a specific node It is possible to force a data to stay in a specific node? -- Everton Lima Aleixo Bacharel em Ciência da Computação pela UFG Mestrando em Ciência da Computação pela UFG Programador no LUPA -- Everton Lima Aleixo Bacharel em Ciência da Computação pela UFG Mestrando em Ciência da Computação pela UFG Programador no LUPA
Re: Force data to a specific node
Hi Dominique, I have the same problem! I would like to place an object in a specific node because I'm working in a spatial application. How should I choose the K1 part to forcing a given object to go to a node? 2013/1/3 DE VITO Dominique dominique.dev...@thalesgroup.com Hi Everton, ** ** AFAIK, the pb is not forcing data to a specific node, but forcing some kind of data locality. ** ** There is things into cql to do it: you define a composite key (K1, K2), and K1 part is used as a rowkey and K2 is used within column name. So, all rows with same K1 are on the same node. ** ** See also https://issues.apache.org/jira/browse/CASSANDRA-5054 ** ** Dominique ** ** ** ** *De :* Everton Lima [mailto:peitin.inu...@gmail.com] *Envoyé :* mercredi 2 janvier 2013 19:20 *À :* user@cassandra.apache.org *Objet :* Re: Force data to a specific node ** ** We need to do this to minimize the network I/O. We have our own load data balance algorithm. We have some data that is best to process in a local machine. Is it possible? How? 2013/1/2 Edward Sargisson edward.sargis...@globalrelay.net Why would you want to? ** ** -- *From*: Everton Lima peitin.inu...@gmail.com *To*: Cassandra-User user@cassandra.apache.org *Sent*: Wed Jan 02 18:03:49 2013 *Subject*: Force data to a specific node It is possible to force a data to stay in a specific node? -- Everton Lima Aleixo Bacharel em Ciência da Computação pela UFG Mestrando em Ciência da Computação pela UFG Programador no LUPA ** ** -- Everton Lima Aleixo Bacharel em Ciência da Computação pela UFG Mestrando em Ciência da Computação pela UFG Programador no LUPA ** ** -- Atenciosamente, Sávio S. Teles de Oliveira voice: +55 62 9136 6996 http://br.linkedin.com/in/savioteles Mestrando em Ciências da Computação - UFG Arquiteto de Software Laboratory for Ubiquitous and Pervasive Applications (LUPA) - UFG
RE: Force data to a specific node
Hi Sávio, There is no definitive response: it depends on your business model ;-) I just guess here it should be something like the id of some data root. Take also a look at http://www.datastax.com/dev/blog/schema-in-cassandra-1-1 and look for partition key, if you want to go through CQL. De : Sávio Teles [mailto:savio.te...@lupa.inf.ufg.br] Envoyé : jeudi 3 janvier 2013 14:58 À : user@cassandra.apache.org Objet : Re: Force data to a specific node Hi Dominique, I have the same problem! I would like to place an object in a specific node because I'm working in a spatial application. How should I choose the K1 part to forcing a given object to go to a node? 2013/1/3 DE VITO Dominique dominique.dev...@thalesgroup.commailto:dominique.dev...@thalesgroup.com Hi Everton, AFAIK, the pb is not forcing data to a specific node, but forcing some kind of data locality. There is things into cql to do it: you define a composite key (K1, K2), and K1 part is used as a rowkey and K2 is used within column name. So, all rows with same K1 are on the same node. See also https://issues.apache.org/jira/browse/CASSANDRA-5054 Dominique De : Everton Lima [mailto:peitin.inu...@gmail.commailto:peitin.inu...@gmail.com] Envoyé : mercredi 2 janvier 2013 19:20 À : user@cassandra.apache.orgmailto:user@cassandra.apache.org Objet : Re: Force data to a specific node We need to do this to minimize the network I/O. We have our own load data balance algorithm. We have some data that is best to process in a local machine. Is it possible? How? 2013/1/2 Edward Sargisson edward.sargis...@globalrelay.netmailto:edward.sargis...@globalrelay.net Why would you want to? From: Everton Lima peitin.inu...@gmail.commailto:peitin.inu...@gmail.com To: Cassandra-User user@cassandra.apache.orgmailto:user@cassandra.apache.org Sent: Wed Jan 02 18:03:49 2013 Subject: Force data to a specific node It is possible to force a data to stay in a specific node? -- Everton Lima Aleixo Bacharel em Ciência da Computação pela UFG Mestrando em Ciência da Computação pela UFG Programador no LUPA -- Everton Lima Aleixo Bacharel em Ciência da Computação pela UFG Mestrando em Ciência da Computação pela UFG Programador no LUPA -- Atenciosamente, Sávio S. Teles de Oliveira voice: +55 62 9136 6996 http://br.linkedin.com/in/savioteles Mestrando em Ciências da Computação - UFG Arquiteto de Software Laboratory for Ubiquitous and Pervasive Applications (LUPA) - UFG
Force data to a specific node
It is possible to force a data to stay in a specific node? -- Everton Lima Aleixo Bacharel em Ciência da Computação pela UFG Mestrando em Ciência da Computação pela UFG Programador no LUPA
Re: Force data to a specific node
Why would you want to? From: Everton Lima peitin.inu...@gmail.com To: Cassandra-User user@cassandra.apache.org Sent: Wed Jan 02 18:03:49 2013 Subject: Force data to a specific node It is possible to force a data to stay in a specific node? -- Everton Lima Aleixo Bacharel em Ciência da Computação pela UFG Mestrando em Ciência da Computação pela UFG Programador no LUPA
Re: Force data to a specific node
We need to do this to minimize the network I/O. We have our own load data balance algorithm. We have some data that is best to process in a local machine. Is it possible? How? 2013/1/2 Edward Sargisson edward.sargis...@globalrelay.net Why would you want to? -- *From*: Everton Lima peitin.inu...@gmail.com *To*: Cassandra-User user@cassandra.apache.org *Sent*: Wed Jan 02 18:03:49 2013 *Subject*: Force data to a specific node It is possible to force a data to stay in a specific node? -- Everton Lima Aleixo Bacharel em Ciência da Computação pela UFG Mestrando em Ciência da Computação pela UFG Programador no LUPA -- Everton Lima Aleixo Bacharel em Ciência da Computação pela UFG Mestrando em Ciência da Computação pela UFG Programador no LUPA
Re: Force data to a specific node
There is a crazy, very bad, don't do it way to do this. You can set RF=1 and hack the LocalPartitioner (because the local partitioner has been made not to do this) Then the node you connect to and write is the node the data will get stored on. Its like memcache do it yourself style sharding. Did I say not suggested. If not not suggested On Wed, Jan 2, 2013 at 2:54 PM, Aaron Turner synfina...@gmail.com wrote: You'd have to use the ordered partitioner or something like that and choose your row key according to the node you want it placed. But that's in general a really bad idea because you end up with unbalanced nodes and hot spots. That said, are your nodes on a LAN? I have my 9+3 node cluster (two datacenters) on 100Mbps ports (which everyone says not to do) and it's working just fine. Even node rebuilds haven't been that bad so far. If you're trying to avoid WAN replication, then use a dedicated cluster. On Wed, Jan 2, 2013 at 10:20 AM, Everton Lima peitin.inu...@gmail.com wrote: We need to do this to minimize the network I/O. We have our own load data balance algorithm. We have some data that is best to process in a local machine. Is it possible? How? 2013/1/2 Edward Sargisson edward.sargis...@globalrelay.net Why would you want to? From: Everton Lima peitin.inu...@gmail.com To: Cassandra-User user@cassandra.apache.org Sent: Wed Jan 02 18:03:49 2013 Subject: Force data to a specific node It is possible to force a data to stay in a specific node? -- Everton Lima Aleixo Bacharel em Ciência da Computação pela UFG Mestrando em Ciência da Computação pela UFG Programador no LUPA -- Everton Lima Aleixo Bacharel em Ciência da Computação pela UFG Mestrando em Ciência da Computação pela UFG Programador no LUPA -- Aaron Turner http://synfin.net/ Twitter: @synfinatic http://tcpreplay.synfin.net/ - Pcap editing and replay tools for Unix Windows Those who would give up essential Liberty, to purchase a little temporary Safety, deserve neither Liberty nor Safety. -- Benjamin Franklin carpe diem quam minimum credula postero
