Hi all,
I'm running HBase 0.19.3 with Hadoop 0.19.1 on a clusters of 2 machines
operating Linux Ubuntu. Files are not being stored inside the /tmp folder.
The problem that already occurred 3 times is that, suddenly, all data stored
in my table is gone after the entire cluster is restarted, either
Hi Lucas!
Just a quick thought. Do you have a lot of data in your cluster or just a
few things in there?
If you don't have that much data in HBase it might not have been flushed to
disk/HDFS yet
and therefore only sits in the internal memcache in HBase, so when your
machines are turned
of, that dat
Hi Erik,
I have only a small amount of data, something between 1500 e 3000 documents.
Is there a way to force a flush of those documents?
1500 to 3000 is the number of new documents that the application I'm
currently working on inserts everyday, so I think it would be nice to flush
them all to di
But isn't it strange that the whole table suddenly became unavailable?
Specially because it's inside HDFS.
Also, I've already created tables with very few rows, 250 for instance, that
kept available after shutting down and starting again HBase. Is it because
when HBase is properly shut data is flu
Hi Lucas!
Yeah, have a look at HBaseAdmin and you will find flush and compact. Not
sure that compact is going to make
a big difference in your case, since you only have one flush or so per day,
but might be nice for you to run it too.
Running a compaction means that all you flushed files will be re
Lucas,
Your table is "missing" because the edits in the META table aren't flush, in
0.20 we "fix" this by setting a very small maximum memcache size on both
ROOT and META tables so that the edits go to disk often. If all the nodes in
your cluster are shutdown at the same moment, another problem th
Hi Lucas!
Not sure if you have had a look at the BigTable paper, link in the beginning
of http://hadoop.apache.org/hbase/ might clear some of the confusion.
But basically what happens is to support fast writes we only write to
memory and periodically flush this data to disk, so while data is still
Helped a lot! Thanks for the replies. I'll keep coding and move to newer
versions of HBase and Hadoop as soon as they are out. I'll also have a look
at the flush operation from HBaseAdmin.
Lucas
On Wed, Jun 17, 2009 at 1:58 PM, Erik Holstad wrote:
> Hi Lucas!
> Not sure if you have had a look
See also 'tools' in the hbase shell. There is a tool to flush all in a
table or an individual region.
I also need to roll a 0.19.4 candidate. It has a few issues that have us
flushing catalog tables way more frequently that we used to.
St.Ack
On Wed, Jun 17, 2009 at 10:04 AM, Lucas Nazário dos
