+1.
2020년 2월 13일 (목) 오전 9:30, Gengliang Wang <gengliang.w...@databricks.com>님이
작성:
> +1, this is really helpful. We should make the SQL configurations
> consistent and more readable.
>
> On Wed, Feb 12, 2020 at 3:33 PM Rubén Berenguel <rbereng...@gmail.com>
> wrote:
>
>> I love it, it will make configs easier to read and write. Thanks Wenchen.
>>
>> R
>>
>> On 13 Feb 2020, at 00:15, Dongjoon Hyun <dongjoon.h...@gmail.com> wrote:
>>
>>
>> Thank you, Wenchen.
>>
>> The new policy looks clear to me. +1 for the explicit policy.
>>
>> So, are we going to revise the existing conf names before 3.0.0 release?
>>
>> Or, is it applied to new up-coming configurations from now?
>>
>> Bests,
>> Dongjoon.
>>
>> On Wed, Feb 12, 2020 at 7:43 AM Wenchen Fan <cloud0...@gmail.com> wrote:
>>
>>> Hi all,
>>>
>>> I'd like to discuss the naming policy of Spark configs, as for now it
>>> depends on personal preference which leads to inconsistent namings.
>>>
>>> In general, the config name should be a noun that describes its meaning
>>> clearly.
>>> Good examples:
>>> spark.sql.session.timeZone
>>> spark.sql.streaming.continuous.executorQueueSize
>>> spark.sql.statistics.histogram.numBins
>>> Bad examples:
>>> spark.sql.defaultSizeInBytes (default size for what?)
>>>
>>> Also note that, config name has many parts, joined by dots. Each part is
>>> a namespace. Don't create namespace unnecessarily.
>>> Good example:
>>> spark.sql.execution.rangeExchange.sampleSizePerPartition
>>> spark.sql.execution.arrow.maxRecordsPerBatch
>>> Bad examples:
>>> spark.sql.windowExec.buffer.in.memory.threshold ("in" is not a useful
>>> namespace, better to be .buffer.inMemoryThreshold)
>>>
>>> For a big feature, usually we need to create an umbrella config to turn
>>> it on/off, and other configs for fine-grained controls. These configs
>>> should share the same namespace, and the umbrella config should be named
>>> like featureName.enabled. For example:
>>> spark.sql.cbo.enabled
>>> spark.sql.cbo.starSchemaDetection
>>> spark.sql.cbo.starJoinFTRatio
>>> spark.sql.cbo.joinReorder.enabled
>>> spark.sql.cbo.joinReorder.dp.threshold （BTW "dp" is not a good
>>> namespace）
>>> spark.sql.cbo.joinReorder.card.weight （BTW "card" is not a good
>>> namespace）
>>>
>>> For boolean configs, in general it should end with a verb, e.g.
>>> spark.sql.join.preferSortMergeJoin. If the config is for a feature and
>>> you can't find a good verb for the feature, featureName.enabled is also
>>> good.
>>>
>>> I'll update https://spark.apache.org/contributing.html after we reach a
>>> consensus here. Any comments are welcome!
>>>
>>> Thanks,
>>> Wenchen
>>>
>>>
>>>
