Re: Client`s cache invalidation

2010-10-01 Thread Naresh Rapolu
If zookeeper isn`t invalidating the client`s cache, then what is the actual use of a zookeeper session? Is it needed only to lookup region-location of the "root-tablet" of META table, which is later used to recursively scan the entire META table ? Can`t that just be a lookup query to zookeeper

RE: Client`s cache invalidation

2010-10-01 Thread Jonathan Gray
Yes. RegionServers will throw a NotServingRegionException. This, in turn, will cause the client to grab the location from META again. > -Original Message- > From: Naresh Rapolu [mailto:nrap...@purdue.edu] > Sent: Friday, October 01, 2010 5:35 PM > To: user@hbase.apache.org > Subject: Cl

Client`s cache invalidation

2010-10-01 Thread Naresh Rapolu
Hello, How does the client`s cache of "region-location"( .META table), get invalidated when a region-server splits regions ? Does Zookeeper abort the client session or inform it of staleness ? How is consistency ensured in the time interval between splits being registered in .META table and

Re: How do I setup authentication/permissions for an hbase database?

2010-10-01 Thread Andrew Purtell
> Is a security feature available that I am not aware of? if > not? what is the point to create a database that can be > edited/deleted by anonymous users? That's kind of a loaded question but I'll bite. Single tenancy is common in systems of this type, which are meant for deployment into back

Re: memstore to blockcache

2010-10-01 Thread Abhijit Pol
thanks bunch stack for the response. agree, we should work towards it. very attractive feature for onlinestore use case of hbase i will open a Jira and as we ramp-up on HBase here, might be able to discuss solutions and potentially work on adding this feature On Fri, Oct 1, 2010 at 8:31 AM, Sta

Re: How do I setup authentication/permissions for an hbase database?

2010-10-01 Thread Gary Helmling
> > Is a security feature available that I am not aware of? if not? what is > the > > point to create a database that can be edited/deleted by anonymous users? > > > > Thats the way it currently works. > > Access control should be here soon though. See HBASE-3025 > > St.Ack > There is now an init

Re: How do I setup authentication/permissions for an hbase database?

2010-10-01 Thread Stack
On Fri, Oct 1, 2010 at 5:04 AM, wrote: > Hello, > > I cannot find any information about secure user access to an hbase database. > > I want to create an hbase database but want to allow only certain users to > access it. > > Currently, anyone can access, write to, delete my tables in my hbase > d

Re: memstore to blockcache

2010-10-01 Thread Stack
Not currently. Blockcache is made of blocks pulled from HDFS. It'd be a little awkward inserting hot records into the block cache w/o going via HDFS. But, yes, you have a good point that flush is disruptive of hot records. In the past we talked of a keyvalue cache on top of the block cache but

How do I setup authentication/permissions for an hbase database?

2010-10-01 Thread acc2
Hello, I cannot find any information about secure user access to an hbase database. I want to create an hbase database but want to allow only certain users to access it. Currently, anyone can access, write to, delete my tables in my hbase database. Is a security feature available that I am

memstore to blockcache

2010-10-01 Thread Abhijit Pol
we are trying to read efficiently a hot column family (in_memory=true, blockcaching=true) that get writes at say 500 qps and reads at 10,000 qps. - as long as writes are in memstore we get them from memstore and its fast - if we have read it once it will be at least in block cache (gets priority d