hbase-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Gary Helmling <ghelml...@gmail.com>
Subject Re: Coprocessors - Only One User Priority Coprocessor Permitted?
Date Fri, 11 Mar 2011 01:12:52 GMT
Hi Jesse,

Yes, the intent is definitely to allow chaining of multiple user
coprocessors for the same table.  If EnvironmentPriorityComparator is
blocking that, that is definitely a bug and we should get it fixed.

Would you mind opening a JIRA for the issue?


On Thu, Mar 10, 2011 at 4:33 PM, Jesse Daniels <jessedaniels1@gmail.com>wrote:

> I’m experimenting with the coprocessor functionality in trunk, specifically
> region observers. The documentation talks about the ability to chain
> coprocessors such that they are called one after another. I noticed in the
> source (CoprocessorHost.java) that coprocessors are added to HBase using a
> TreeSet that is initialized with an EnvironmentPriorityComparator. I’m
> discovering that the net effect of this is that only one “User” priority
> coprocessor can be loaded at a time. This appears to be due to how the
> TreeSet uses the EnvironmentPriorityComparator to determine whether there
> are duplicate entries – if the coprocessors have the same priority (e.g.,
> User), they are considered the same and won’t be added to the Set. I'm
> guessing this isn't the desired behavior? I originally assumed that you
> could have multiple user coprocessors per table and therefore the
> comparator
> should be by class name or something more unique.
> Thanks for your insight.

  • Unnamed multipart/alternative (inline, None, 0 bytes)
View raw message