So I have set the heap to 12Gb and the memstore limit to upperLimit .5
lowerLimit .45. I am not seeing any changes in behavior from the cluster so
far, i have restarted 4/17 region servers. Do I need to restart master for the
memstore to take effect? Also how do I enable logging to show why a region is
being flushed? I don’t ever seen the region flushes in my logs.
Thanks,
Pere
On Nov 6, 2014, at 7:12 AM, Ted Yu <yuzhih...@gmail.com> wrote:
> bq. to increase heap and increase the memstore limit?
>
> Yes. That would be an action that bears fruit.
> Long term, you should merge the small regions.
>
> Cheers
>
> On Wed, Nov 5, 2014 at 11:20 PM, Pere Kyle <p...@whisper.sh> wrote:
>
>> Watching closely a region server in action. It seems that the memstores
>> are being flushed at around 2MB on the regions. This would seem to
>> indicate that there is not enough heap for the memstore and I am hitting
>> the upper bound of limit (default). Would this be a fair assumption? Should
>> I look to increase heap and increase the memstore limit?
>>
>> Thanks!
>> -Pere
>>
>> On Nov 5, 2014, at 10:26 PM, Ted Yu <yuzhih...@gmail.com> wrote:
>>
>>> You can use ConstantSizeRegionSplitPolicy.
>>> Split policy can be specified per table. See the following example
>>> in create.rb :
>>>
>>> hbase> create 't1', 'f1', {NUMREGIONS => 15, SPLITALGO =>
>>> 'HexStringSplit'}
>>>
>>> In 0.94.18, there isn't online merge. So you have to use other method to
>>> merge the small regions.
>>>
>>> Cheers
>>>
>>> On Wed, Nov 5, 2014 at 10:14 PM, Pere Kyle <p...@whisper.sh> wrote:
>>>
>>>> Ted,
>>>>
>>>> Thanks so much for that information. I now see why this split too often,
>>>> but what I am not sure of is how to fix this without blowing away the
>>>> cluster. Add more heap?
>>>>
>>>> Another symptom I have noticed is that load on the Master instance hbase
>>>> daemon has been pretty high (load average 4.0, whereas it used to be
>> 1.0)
>>>>
>>>> Thanks,
>>>> Pere
>>>>
>>>> On Nov 5, 2014, at 9:56 PM, Ted Yu <yuzhih...@gmail.com> wrote:
>>>>
>>>>> IncreasingToUpperBoundRegionSplitPolicy is the default split policy.
>>>>>
>>>>> You can read the javadoc of this class to see how it works.
>>>>>
>>>>> Cheers
>>>>>
>>>>> On Wed, Nov 5, 2014 at 9:39 PM, Ted Yu <yuzhih...@gmail.com> wrote:
>>>>>
>>>>>> Can you provide a bit more information (such as HBase release) ?
>>>>>>
>>>>>> If you pastebin one of the region servers' log, that would help us
>>>>>> determine the cause.
>>>>>>
>>>>>> Cheers
>>>>>>
>>>>>>
>>>>>> On Wed, Nov 5, 2014 at 9:29 PM, Pere Kyle <p...@whisper.sh> wrote:
>>>>>>
>>>>>>> Hello,
>>>>>>>
>>>>>>> Recently our cluster which has been running fine for 2 weeks split to
>>>>>>> 1024 regions at 1GB per region, after this split the cluster is
>>>> unusable.
>>>>>>> Using the performance benchmark I was getting a little better than
>> 100
>>>> w/s,
>>>>>>> whereas before it was 5000 w/s. There are 15 nodes of m2.2xlarge with
>>>> 8GB
>>>>>>> heap reserved for Hbase
>>>>>>>
>>>>>>> Any Ideas? I am stumped:
>>>>>>>
>>>>>>> Thanks,
>>>>>>> Pere
>>>>>>>
>>>>>>> Here is the current
>>>>>>> hbase-site.xml
>>>>>>> <?xml version="1.0"?>
>>>>>>> <?xml-stylesheet type="text/xsl" href="configuration.xsl"?>
>>>>>>> <configuration>
>>>>>>> <property>
>>>>>>> <name>hbase.snapshot.enabled</name>
>>>>>>> <value>true</value>
>>>>>>> </property>
>>>>>>>
>>>>>>>
>>>>
>> <property><name>fs.hdfs.impl</name><value>emr.hbase.fs.BlockableFileSystem</value></property>
>>>>>>>
>>>>>>>
>>>>
>> <property><name>hbase.regionserver.handler.count</name><value>50</value></property>
>>>>>>>
>>>>>>>
>>>>
>> <property><name>hbase.cluster.distributed</name><value>true</value></property>
>>>>>>>
>>>>>>>
>>>>
>> <property><name>hbase.tmp.dir</name><value>/mnt/var/lib/hbase/tmp-data</value></property>
>>>>>>>
>>>>>>>
>>>>
>> <property><name>hbase.master.wait.for.log.splitting</name><value>true</value></property>
>>>>>>>
>>>>>>>
>>>>
>> <property><name>hbase.hregion.memstore.flush.size</name><value>134217728</value></property>
>>>>>>> <property><name>hbase.hregion.max.filesize</name><value>5073741824
>>>>>>> </value></property>
>>>>>>>
>>>>>>>
>>>>
>> <property><name>zookeeper.session.timeout</name><value>60000</value></property>
>>>>>>>
>>>>>>>
>>>>
>> <property><name>hbase.thrift.maxQueuedRequests</name><value>0</value></property>
>>>>>>>
>>>>>>>
>>>>
>> <property><name>hbase.client.scanner.caching</name><value>1000</value></property>
>>>>>>>
>>>>>>>
>>>>
>> <property><name>hbase.hregion.memstore.block.multiplier</name><value>4</value></property>
>>>>>>> </configuration>
>>>>>>>
>>>>>>> hbase-env.sh
>>>>>>> # The maximum amount of heap to use, in MB. Default is 1000.
>>>>>>> export HBASE_HEAPSIZE=8000
>>>>>>>
>>>>>>> # Extra Java runtime options.
>>>>>>> # Below are what we set by default. May only work with SUN JVM.
>>>>>>> # For more on why as well as other possible settings,
>>>>>>> # see http://wiki.apache.org/hadoop/PerformanceTuning
>>>>>>> export HBASE_OPTS="-XX:+UseConcMarkSweepGC”
>>>>>>>
>>>>>>> hbase-env.sh
>>>>>>
>>>>>>
>>>>>>
>>>>
>>>>
>>
>>
