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:
> I want to know how RS eliminates the unnecessary hlogs.
> lastSeqNum stores <RegionName, latest KV Seq id>
> 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.
> Bing Jiang
> 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