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Duo Zhang commented on HBASE-18715: ----------------------------------- [~javaman_chen] Why mark it as resolved? We haven't committed the patch yet... > isolate large query > ------------------- > > Key: HBASE-18715 > URL: https://issues.apache.org/jira/browse/HBASE-18715 > Project: HBase > Issue Type: New Feature > Reporter: chenxu > Assignee: chenxu > Attachments: HBASE-18715-master-v1.patch, > HBASE-18715-master-v2.patch, HBASE-18715-master-v3.patch, > HBASE-18715-master-v4.patch, isolate large query.pdf, isolate result.png > > > large queries are very expensive than the general operation, and often delay > insensitive. > if not isolate, Handlers may be all used by the large query, > lead to _Put_ or _Get_ slowly, so there need be an mechanism to isolate the > large query. > for example we can use a separate _RpcExecutor_ to handle this. > for the following type of queries we can think it is a large query: > (1) _Scan_ has no startkey or endkey > (2) Client call _ResultScanner.next()_ more than a certain threshold > (3) Client call custom coprocessor which involves large queries(such as > _AggregateService_) > for large queries, RegionServer should meet the following requirements > (1) dynamic configure if isolate large query is turn on > (2) setup certain Handlers to deal with large queries only > (3) in offpeak hours, large queries are not isolate > (4) dynamic configure if cache Blocks is turn on if the query is a large query -- This message was sent by Atlassian JIRA (v6.4.14#64029)