Re: In memory table after using 'alter'

2012-06-28 Thread Minh Duc Nguyen
Sever, I'd say that the wiki page is incomplete when discussing bloom filters. The HBase Reference Guide http://hbase.apache.org/book.html#schema.bloom provides a much better explanation of the different bloom filter options. ~ Minh On Thu, Jun 28, 2012 at 9:54 AM, Sever Fundatureanu wrote

Re: In memory table after using 'alter'

2012-06-28 Thread Sever Fundatureanu
Thanks, Minh. This blog also mentions that bloom filters check "if a given column exists in a given row". However in "HBase: The definitive guide" it is mentioned that "enabling the Bloom filter does give you the immediate advantage of knowing if a file contains a particular row key or not". Is the

Re: In memory table after using 'alter'

2012-06-27 Thread Minh Duc Nguyen
Sever, the IN_MEMORY option doesn't change when table content is transferred into RAM. Whether set to true or false, the blocks of data are only loaded into memory after a normal retrieval operation. When IN_MEMORY is set to true, HBase just tries to keep data in memory more aggressively than it n

In memory table after using 'alter'

2012-06-27 Thread Sever Fundatureanu
Hello, I initially created a table without the IN_MEMORY option enabled and loaded some data into it. Then I disabled it, modified the IN_MEMORY option using the hbase shell 'alter' command, re-enabled it and finally ran a major compaction. I do notice now the memory usage of the region servers ha