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https://issues.apache.org/jira/browse/HBASE-11208?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14086523#comment-14086523
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Lars Hofhansl commented on HBASE-11208:
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There are two issues: OOMs and read performance.
We'd then need another way than to "configure" HBase for read vs. write loads.
This setting is what puts an upper bound on acceptable read performance by
limiting the number of HFiles a scan has to look through - at the expense of
blocking writers if they write faster than the IO subsystem can absorb. The key
is some mechanism to force HBase to slow clients down or block them completely
from writing if some "guaranteed" read performance is desired.
> Remove the hbase.hstore.blockingStoreFiles setting
> --------------------------------------------------
>
> Key: HBASE-11208
> URL: https://issues.apache.org/jira/browse/HBASE-11208
> Project: HBase
> Issue Type: Brainstorming
> Components: Compaction, regionserver
> Affects Versions: 0.99.0
> Reporter: Nicolas Liochon
> Assignee: Nicolas Liochon
> Fix For: 0.99.0
>
>
> It's a little bit of a provocation, but the rational is:
> - there are some bugs around the delayed flush. For example, if the periodic
> scheduler has asked for a delayed flush, and that we need to flush, we will
> have to wait
> - if the number of WAL files increases, we won't flush immediately if the
> blockingFile number has been reached. This impacts the MTTR.
> - We don't write to limit the compaction impact, but they are many cases
> where we would want to flush anyway, as the writes cannot wait.
> - this obviously leads to huge write latency peaks.
> So I'm questioning this setting, it leads to multiple intricate cases,
> unpredictable write latency, and looks like a workaround for compaction
> performances. With all the work done on compaction, I think we can get rid of
> it. A solution in the middle would be to deprecate it and to set it to a
> large value...
> Any opinion before I shoot :-) ?
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