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HBase >> mail # user >> Risk about RS logs clean ?


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Re: Risk about RS logs clean ?
FSHLog (in trunk) stores the earliest seqnums for each region in current
memstore, and earliest flushing seqnum (see
FSHLog::start/complete/abortCacheFlush). When logs are deleted the logs
with seqnums that are above the earliest flushing/flushed seqnum for any
region are not deleted (see FSHLog::cleanOldLogs).

On Wed, May 22, 2013 at 5:39 AM, Bing Jiang <[EMAIL PROTECTED]>wrote:

> Hi,all
> I want to know how RS eliminates the unnecessary hlogs.
> lastSeqNum stores <RegionName, latest KV Seq id>
> and
> outputfiles stores <last Seq id before new hlog file, file path>
>
> So, how does rs guarantee that the kv in the hlog to be cleared  have been
> already flushed from memstore into hfile.
> I have try to read source code to make sense, however, I am not sure
> whether it is a source of the risk of data loss.
>
> Thanks.
> --
> Bing Jiang
> Tel:(86)134-2619-1361
> weibo: http://weibo.com/jiangbinglover
> BLOG: http://blog.sina.com.cn/jiangbinglover
> National Research Center for Intelligent Computing Systems
> Institute of Computing technology
> Graduate University of Chinese Academy of Science
>
NEW: Monitor These Apps!
elasticsearch, apache solr, apache hbase, hadoop, redis, casssandra, amazon cloudwatch, mysql, memcached, apache kafka, apache zookeeper, apache storm, ubuntu, centOS, red hat, debian, puppet labs, java, senseiDB