helix-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From ShaoFeng Shi <shaofeng...@apache.org>
Subject Re: Mapping from a resource partition to a logical data partition
Date Fri, 05 Feb 2016 12:52:29 GMT
I see there is a JIRA HELIX-132
<https://issues.apache.org/jira/browse/HELIX-132> which has fixed that
issue in 0.7.1; but from my case, after drop the resource and add back, the
external view still has the old partitions (got from helix-admin.sh),
interesting...

2016-02-05 10:49 GMT+08:00 ShaoFeng Shi <shaofengshi@apache.org>:

> I didn't; But after add the transitions between Dropped and Offline, it
> got the same behavior.
> I also changed my code to drop the resource and create again when its
> partition number reaches a limit; But the external view wasn't deleted,
> that makes Helix thought all the partitions have already been propery
> assigned; Following is a state after the resoruce be recreated, you can see
> although its "NUM_PARTITIONS" is 8, the partitions in external view is 20
> (which is the up limit):
>
> IdealState for Resource_Stream:
> {
>   "id" : "Resource_Stream",
>   "mapFields" : {
>     "Resource_Stream_0" : {
>     },
>     "Resource_Stream_1" : {
>     },
>     "Resource_Stream_10" : {
>     },
>     "Resource_Stream_11" : {
>     },
>     "Resource_Stream_12" : {
>     },
>     "Resource_Stream_13" : {
>     },
>     "Resource_Stream_14" : {
>     },
>     "Resource_Stream_15" : {
>     },
>     "Resource_Stream_16" : {
>     },
>     "Resource_Stream_17" : {
>     },
>     "Resource_Stream_18" : {
>     },
>     "Resource_Stream_19" : {
>     },
>     "Resource_Stream_2" : {
>     },
>     "Resource_Stream_3" : {
>     },
>     "Resource_Stream_4" : {
>     },
>     "Resource_Stream_5" : {
>     },
>     "Resource_Stream_6" : {
>     },
>     "Resource_Stream_7" : {
>     },
>     "Resource_Stream_8" : {
>     },
>     "Resource_Stream_9" : {
>     }
>   },
>   "listFields" : {
>     "Resource_Stream_0" : [ ],
>     "Resource_Stream_1" : [ ],
>     "Resource_Stream_10" : [ ],
>     "Resource_Stream_11" : [ ],
>     "Resource_Stream_12" : [ ],
>     "Resource_Stream_13" : [ ],
>     "Resource_Stream_14" : [ ],
>     "Resource_Stream_15" : [ ],
>     "Resource_Stream_16" : [ ],
>     "Resource_Stream_17" : [ ],
>     "Resource_Stream_18" : [ ],
>     "Resource_Stream_19" : [ ],
>     "Resource_Stream_2" : [ ],
>     "Resource_Stream_3" : [ ],
>     "Resource_Stream_4" : [ ],
>     "Resource_Stream_5" : [ ],
>     "Resource_Stream_6" : [ ],
>     "Resource_Stream_7" : [ ],
>     "Resource_Stream_8" : [ ],
>     "Resource_Stream_9" : [ ]
>   },
>   "simpleFields" : {
>     "IDEAL_STATE_MODE" : "AUTO_REBALANCE",
>     "INSTANCE_GROUP_TAG" : "Tag_StreamBuilder",
>     "NUM_PARTITIONS" : "8",
>     "REBALANCE_MODE" : "FULL_AUTO",
>     "REPLICAS" : "2",
>     "STATE_MODEL_DEF_REF" : "LeaderStandby",
>     "STATE_MODEL_FACTORY_NAME" : "DEFAULT"
>   }
> }
>
> ExternalView for Resource_Stream:
> {
>   "id" : "Resource_Stream",
>   "mapFields" : {
>     "Resource_Stream_0" : {
>       "kylin-dev3-eaz-969995.phx01.eaz.ebayc3.com_8080" : "LEADER",
>       "kylin-dev4-eaz-687945.phx01.eaz.ebayc3.com_8080" : "STANDBY"
>     },
>     "Resource_Stream_1" : {
>       "kylin-dev3-eaz-969995.phx01.eaz.ebayc3.com_8080" : "STANDBY",
>       "kylin-dev4-eaz-687945.phx01.eaz.ebayc3.com_8080" : "LEADER"
>     },
>     "Resource_Stream_10" : {
>       "kylin-dev3-eaz-969995.phx01.eaz.ebayc3.com_8080" : "LEADER",
>       "kylin-dev4-eaz-687945.phx01.eaz.ebayc3.com_8080" : "STANDBY"
>     },
>     "Resource_Stream_11" : {
>       "kylin-dev3-eaz-969995.phx01.eaz.ebayc3.com_8080" : "STANDBY",
>       "kylin-dev4-eaz-687945.phx01.eaz.ebayc3.com_8080" : "LEADER"
>     },
>     "Resource_Stream_12" : {
>       "kylin-dev3-eaz-969995.phx01.eaz.ebayc3.com_8080" : "LEADER",
>       "kylin-dev4-eaz-687945.phx01.eaz.ebayc3.com_8080" : "STANDBY"
>     },
>     "Resource_Stream_13" : {
>       "kylin-dev3-eaz-969995.phx01.eaz.ebayc3.com_8080" : "STANDBY",
>       "kylin-dev4-eaz-687945.phx01.eaz.ebayc3.com_8080" : "LEADER"
>     },
>     "Resource_Stream_14" : {
>       "kylin-dev3-eaz-969995.phx01.eaz.ebayc3.com_8080" : "LEADER",
>       "kylin-dev4-eaz-687945.phx01.eaz.ebayc3.com_8080" : "STANDBY"
>     },
>     "Resource_Stream_15" : {
>       "kylin-dev3-eaz-969995.phx01.eaz.ebayc3.com_8080" : "STANDBY",
>       "kylin-dev4-eaz-687945.phx01.eaz.ebayc3.com_8080" : "LEADER"
>     },
>     "Resource_Stream_16" : {
>       "kylin-dev3-eaz-969995.phx01.eaz.ebayc3.com_8080" : "LEADER",
>       "kylin-dev4-eaz-687945.phx01.eaz.ebayc3.com_8080" : "STANDBY"
>     },
>     "Resource_Stream_17" : {
>       "kylin-dev3-eaz-969995.phx01.eaz.ebayc3.com_8080" : "STANDBY",
>       "kylin-dev4-eaz-687945.phx01.eaz.ebayc3.com_8080" : "LEADER"
>     },
>     "Resource_Stream_18" : {
>       "kylin-dev3-eaz-969995.phx01.eaz.ebayc3.com_8080" : "LEADER",
>       "kylin-dev4-eaz-687945.phx01.eaz.ebayc3.com_8080" : "STANDBY"
>     },
>     "Resource_Stream_19" : {
>       "kylin-dev3-eaz-969995.phx01.eaz.ebayc3.com_8080" : "STANDBY",
>       "kylin-dev4-eaz-687945.phx01.eaz.ebayc3.com_8080" : "LEADER"
>     },
>     "Resource_Stream_2" : {
>       "kylin-dev3-eaz-969995.phx01.eaz.ebayc3.com_8080" : "LEADER",
>       "kylin-dev4-eaz-687945.phx01.eaz.ebayc3.com_8080" : "STANDBY"
>     },
>     "Resource_Stream_3" : {
>       "kylin-dev3-eaz-969995.phx01.eaz.ebayc3.com_8080" : "STANDBY",
>       "kylin-dev4-eaz-687945.phx01.eaz.ebayc3.com_8080" : "LEADER"
>     },
>     "Resource_Stream_4" : {
>       "kylin-dev3-eaz-969995.phx01.eaz.ebayc3.com_8080" : "LEADER",
>       "kylin-dev4-eaz-687945.phx01.eaz.ebayc3.com_8080" : "STANDBY"
>     },
>     "Resource_Stream_5" : {
>       "kylin-dev3-eaz-969995.phx01.eaz.ebayc3.com_8080" : "STANDBY",
>       "kylin-dev4-eaz-687945.phx01.eaz.ebayc3.com_8080" : "LEADER"
>     },
>     "Resource_Stream_6" : {
>       "kylin-dev3-eaz-969995.phx01.eaz.ebayc3.com_8080" : "LEADER",
>       "kylin-dev4-eaz-687945.phx01.eaz.ebayc3.com_8080" : "STANDBY"
>     },
>     "Resource_Stream_7" : {
>       "kylin-dev3-eaz-969995.phx01.eaz.ebayc3.com_8080" : "STANDBY",
>       "kylin-dev4-eaz-687945.phx01.eaz.ebayc3.com_8080" : "LEADER"
>     },
>     "Resource_Stream_8" : {
>       "kylin-dev3-eaz-969995.phx01.eaz.ebayc3.com_8080" : "LEADER",
>       "kylin-dev4-eaz-687945.phx01.eaz.ebayc3.com_8080" : "STANDBY"
>     },
>     "Resource_Stream_9" : {
>       "kylin-dev3-eaz-969995.phx01.eaz.ebayc3.com_8080" : "STANDBY",
>       "kylin-dev4-eaz-687945.phx01.eaz.ebayc3.com_8080" : "LEADER"
>     }
>   },
>   "listFields" : {
>   },
>   "simpleFields" : {
>     "BUCKET_SIZE" : "0"
>   }
> }
>
> 2016-02-04 23:08 GMT+08:00 kishore g <g.kishore@gmail.com>:
>
>> Ha ave you defined offline to dropped state transition in your state
>> transition handler.
>> On Feb 3, 2016 11:31 PM, "ShaoFeng Shi" <shaofengshi@apache.org> wrote:
>>
>>> I found an issue: the numberOfPartitions can only be increased, and
>>> couldn't be decreased; Even if I set it to 0, and then do a rebalance, the
>>> old partitions still exist in idea view and external view; So, how can
>>> descrease or drop a partition?
>>>
>>>
>>>
>>> 2016-02-04 15:28 GMT+08:00 ShaoFeng Shi <shaofengshi@apache.org>:
>>>
>>>> Nice, that you Kishore!
>>>>
>>>> 2016-02-04 10:35 GMT+08:00 kishore g <g.kishore@gmail.com>:
>>>>
>>>>> This is needed for another project I am working on. There is no reason
>>>>> for Helix to depend on this convention. I will fix this.
>>>>>
>>>>>
>>>>>
>>>>> On Wed, Feb 3, 2016 at 5:51 PM, ShaoFeng Shi <shaofengshi@apache.org>
>>>>> wrote:
>>>>>
>>>>>> Hello,
>>>>>>
>>>>>> I'm trying to use Helix (0.7.1) to manage our resource partitions
on a
>>>>>> cluster. My scenario is, every 5 minutes a partition will be added;
>>>>>> What I
>>>>>> do now is, get the ideal state, +1 for the partition number and then
>>>>>> update
>>>>>> it with ZKHelixAdmin. With a rebalance action, the new partition
will
>>>>>> be
>>>>>> created and assigned to an instance. What the instance can get from
>>>>>> Helix
>>>>>> is the resource name and partition id. To map the parition to my
>>>>>> logical
>>>>>> data, I maintained a mapping table in our datastore, which looks
like:
>>>>>>
>>>>>> {
>>>>>>   "resource_0": 201601010000_ 201601010005,
>>>>>>   "resource_1": 201601010005_ 201601010010,
>>>>>>   ...
>>>>>>   "resource_11": 201601010055_ 201601010100
>>>>>> }
>>>>>>
>>>>>> Here it has 12 partitions; Now I want to discard some old partitions,
>>>>>> say
>>>>>> the first 6 partitions;  It seems in Helix the partitions must start
>>>>>> from
>>>>>> 0, so with an update on the IdealState, set # of partitions to 6,
the
>>>>>> new
>>>>>> partitions on the cluster would become to:
>>>>>>
>>>>>> resource_0,resource_1, ..., resource_5,
>>>>>>
>>>>>> To make sure the partitions wouldn't be wrongly mapped, I need update
>>>>>> my
>>>>>> mapping table before the rebalance. While that may not ensure the
>>>>>> atomic
>>>>>> between the two updates.
>>>>>>
>>>>>> So my question is, what's the suggested way to do the resource
>>>>>> partition
>>>>>> mapping? does Helix allow user to specify additional information
on a
>>>>>> partition (if have this, I don't need maintain the mapping outside)?
>>>>>> Can we
>>>>>> have some simple APIs like addPartition(String parititionName),
>>>>>> dropParitition(String partitionName), just like that for resource?
The
>>>>>> numeric paritition id can be an internal ID and not exposed to user.
>>>>>>
>>>>>> I guess many entry users will have such questions. Just raise this
>>>>>> for a
>>>>>> broad discussion; Any comment and suggestion is welcomed. Thanks
for
>>>>>> your
>>>>>> time!
>>>>>>
>>>>>>
>>>>>> --
>>>>>> Best regards,
>>>>>>
>>>>>> Shaofeng Shi
>>>>>>
>>>>>
>>>>>
>>>>
>>>>
>>>> --
>>>> Best regards,
>>>>
>>>> Shaofeng Shi
>>>>
>>>>
>>>
>>>
>>> --
>>> Best regards,
>>>
>>> Shaofeng Shi
>>>
>>>
>
>
> --
> Best regards,
>
> Shaofeng Shi
>
>


-- 
Best regards,

Shaofeng Shi

Mime
View raw message