Hi JS.
Here are some hints to help you debug:
- make sure you have the jar copied to all the region servers if you
want it to sit on local fs, or you can put it to hdfs so all RS can
access it without copying arount.
- remember to disable, and enable the table to make sure the attribute
be loaded
- if you still cannot see it working, please post your RS log after the
time of table enabled.
Loading cp classes from file system lacks of testing, so there might be
some issues. I added a jira:
https://issues.apache.org/jira/browse/HBASE-3516 to add test cases back
for class loading.
Another workaround is to use configuration to test your coprocessor.
This has been tested a lot among us. The only problem is that it would
be applied to all your tables. You can use this method if there is an
issue for cp class loading from jar files.
Thanks,
Mingjie
On 02/08/2011 10:01 AM, [email protected] wrote:
Hi,
thanks for your feedback!
Just a follow up question;
According to the TableDescriptor
{NAME => 'test3', Coprocessor$2 => '/Users/hbase/CP.jar:Coprocessor.PreGet:12',
Coprocessor$1 => '/Users/hbase/CP.jar:Coprocessor.PrePut:10',
FAMILIES => [{NAME => 'cf', BLOOMFILTER => 'NONE', REPLICATION_SCOPE => '0', COMPRESSION
=> 'NONE', VERSIONS => '3', TTL => '2147483647', BLOCKSIZE => '65536', IN_MEMORY =>
'false', BLOCKCACHE => 'true'}]}
the coprocessors is specified, but actually neither of them is executed when
executing a put; So I am not sure whether they are actually loaded (what happens
if if jar file is not found? -> this should trigger at least a warning).
Any ideas/pointers why this fails (HBAse Version 0.91.0-SNAPSHOT, r1065918)?
package Coprocessor;
public class PrePut extends BaseRegionObserverCoprocessor {
@Override
public void prePut( RegionCoprocessorEnvironment e, Map<byte[],
List<KeyValue>> familyMap, boolean writeToWAL) throws IOException {
//bypass normal system call
e.bypass();
}
}
Thanks again!
JS
-----Ursprüngliche Nachricht-----
Von: "Andrew Purtell"<[email protected]>
Gesendet: 07.02.2011 23:42:35
An: [email protected]
Betreff: Re: Loaded Coprocessor
is there any way to check which Coprocessors Classes are
currently loaded? Preferebly using the shell...
Not yet. Good idea, filed: https://issues.apache.org/jira/browse/HBASE-3512
And related: Can one dynamically load Coprocessors for a
running hbase system?
Currently coprocessors are loaded statically via configuration or dynamically upon table
open if there are any table attributes that specify it (attribute name begins with
"Coprocessor"). IIRC the javadoc on the coprocessors package contains detail on
this. In short:
HTableDescriptor htd;
// ...
htd.setValue("Coprocessor$foo",
"hdfs://namenode:port/path/to/coprocessor.jar");
A table descriptor can be updated if such specifications are not made a table
create time. See javadoc for HBaseAdmin.
However there is currently no mechanism for triggering additional loads on
tables already open or loading at arbitrary times. There hasn't been a clearly
articulated need for this yet.
Best regards,
- Andy
Problems worthy of attack prove their worth by hitting back.
- Piet Hein (via Tom White)
--- On Mon, 2/7/11, [email protected]<[email protected]> wrote:
From: [email protected]<[email protected]>
Subject: Loaded Coprocessor
To: [email protected]
Date: Monday, February 7, 2011, 1:48 AM
Hi,
is there any way to check which Coprocessors Classes are
currently loaded? Preferebly using the shell...
And related: Can one dynamically load Coprocessors for a
running hbase system?
Thanks for your support!
JS
