That configuration is more like what 2357 would be used for. You wrote: "that you could route all requests for X to the place where X is when you don't want to have X cached"
And it's for that case that I say you should not go through the nodes and talk directly to the RS. J-D On Tue, Apr 19, 2011 at 2:36 PM, Otis Gospodnetic <[email protected]> wrote: > To make Configuration 4 possible (last slide in > http://www.edwardcapriolo.com/roller/edwardcapriolo/resource/memcache.odp ) -- > Big Request Load, not so Big Data. > > Otis > -- > We're hiring HBase hackers for Data Mining and Analytics > http://blog.sematext.com/2011/04/18/hiring-data-mining-analytics-machine-learning-hackers/ > > > > > ----- Original Message ---- >> From: Jean-Daniel Cryans <[email protected]> >> To: [email protected] >> Sent: Tue, April 19, 2011 5:28:46 PM >> Subject: Re: Region replication? >> >> I don't know why you would want to serve from other region servers if >> all they did was transferring data, the current situation would be >> better. >> >> J-D >> >> On Tue, Apr 19, 2011 at 2:26 PM, Otis Gospodnetic >> <[email protected]> wrote: >> > Thanks J-D! >> > >> > Yeah, what you describe below is also something that I think Edward >> > pointed >>out >> > in some of his slides - that you could route all requests for X to the > place >> > where X is when you don't want to have X cached (in app-level caches >> > and/or >> > OS-level caches) on multiple servers, but that sometimes you do want to >>"waste" >> > memory like this because you have to spread requests for X over more >>servers. >> > >> > Are these two modes going to be supported in HBase? >> > >> > Thanks, >> > Otis >> > ---- >> > We're hiring HBase hackers for Data Mining and Analytics >> > >>http://blog.sematext.com/2011/04/18/hiring-data-mining-analytics-machine-learning-hackers/ >> >> > >> > >> > >> > >> > >> > ----- Original Message ---- >> >> From: Jean-Daniel Cryans <[email protected]> >> >> To: [email protected] >> >> Sent: Tue, April 19, 2011 5:10:07 PM >> >> Subject: Re: Region replication? >> >> >> >> We have something on the menu: >> >> https://issues.apache.org/jira/browse/HBASE-2357 Coprocessors: Add >> >> read-only region replicas (slaves) for availability and fast region >> >> recovery >> >> >> >> Something to keep in mind is that you have to cache the data for each >> >> replica, so a row could be in 3 different caches (which also have to >> >> be warmed). I guess this is useful for very hot rows compared to a >> >> much larger read distribution, in which case you'd really want to >> >> cache it only once else you'd need 3x the memory to hold your dataset >> >> in cache. >> >> >> >> J-D >> >> >> >> On Tue, Apr 19, 2011 at 12:33 PM, Otis Gospodnetic >> >> <[email protected]> wrote: >> >> > Hi, >> >> > >> >> > I imagine lots of HBase folks have read or will want to read >> >> > >>http://blog.milford.io/2011/04/why-i-am-very-excited-about-datastaxs-brisk/ >> > , >> >> > including comments. >> >> > >> >> > My question has to do with one of the good comments from Edward >>Capriolo, >> >>who >> >> > pointed out that some of the Configurations he described in his >>Cassandra >> >> as >> >> > Memcached talk ( >> >> > http://www.edwardcapriolo.com/roller/edwardcapriolo/resource/memcache.odp >>) >> >>are >> >> > not possible with HBase because in HBase there is only 1 copy of any >> given >> >> > Region and it lives on a single RegionServer (I'm assuming this is >> >>correct?), >> >> > thus making it impossible to spread reads of data from one Region >> >> > over >> >>multiple >> >> > RegionServers: >> >> > >> >> > >>>>http://blog.milford.io/2011/04/why-i-am-very-excited-about-datastaxs-brisk/#comment-187253604 >>4 >> >> >> >> > >> >> > >> >> > So I poked around on search-hadoop.com and JIRA, and looked at >> >> > http://hbase.apache.org/book/regions.arch.html to see about this >> > limitation, >> >> > whether it's even mentioned as a limitation, whether there are plans >> >> > to >> >>change >> >> > it or if there are some configuration alternatives that would make >> >> > some >>of >> >>those >> >> > configurations described by Ed possible with HBase, but I actually >>didn't >> >>find >> >> > any explicit information about that. >> >> > >> >> > Would anyone care to comment? :) >> >> > >> >> > Many thanks, >> >> > Otis >> >> > -- >> >> > We're hiring HBase hackers for Data Mining and Analytics >> >> > >>>>http://blog.sematext.com/2011/04/18/hiring-data-mining-analytics-machine-learning-hackers/ >>/ >> >> >> >> > >> >> >> > >> >
