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HBase >> mail # user >> Performance penalty: Custom Filter names serialization


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Re: Performance penalty: Custom Filter names serialization
Hi everyone,

I'm facing the same issue as Pablo. Renaming my classes used in HBase
context improved network usage more than 20%. It would be really nice to
have an improvement around this.

On 08/20/2013 01:15 PM, Jean-Marc Spaggiari wrote:
> But even if we are using Protobuf, he is going to face the same issue,
> right?
>
> We should have a way to send the filter once with a number to say to the
> regions that this filter, moving forward, will be represented by this
> number. There is some risk to re-use a number of a filter already using it,
> but I'm sure we can come with some mechanism to avoid that.
>
> 2013/8/20 Ted Yu <[EMAIL PROTECTED]>
>
>> Are you using HBase 0.92 or 0.94 ?
>>
>> In 0.95 and later releases, HbaseObjectWritable doesn't exist. Protobuf is
>> used for communication.
>>
>> Cheers
>>
>>
>> On Tue, Aug 20, 2013 at 8:56 AM, Pablo Medina <[EMAIL PROTECTED]
>>> wrote:
>>> Hi all,
>>>
>>> I'm using custom filters to retrieve filtered data from HBase using the
>>> native api. I noticed that the class full names of those custom filters
>> is
>>> being sent as the bytes representation of the string using
>>> Text.writeString(). This consumes a lot of network bandwidth in my case
>> due
>>> to using 5 custom filters per Get and issuing 1.5 million gets per
>> minute.
>>> I took at look at the code
>> (org.apache.hadoop.hbase.io.HbaseObjectWritable)
>>> and It seems that HBase registers its known classes (Get, Put, etc...)
>> and
>>> associates them with an Integer (CODE_TO_CLASS and CLASS_TO_CODE). That
>>> integer is sent instead of the full class name for those known classes. I
>>> did a test reducing my custom filter class names to 2 or 3 letters and it
>>> improved my performance in 25%.
>>> Is there any way to "register" my custom filter classes to behave the
>> same
>>> as HBase's classes? If not, does it make sense to introduce a change to
>> do
>>> that? Is there any other workaround for this issue?
>>>
>>> Thanks!
>>>