wal相关配置梳理

<property>
<name>hbase.regionserver.separate.hlog.for.meta</name>
<value>false</value>
<description>是否将meta表region的wal存入单独的HLog中，会添加.meta的文件扩展名</description>
</property>


<property>
<name>hbase.regionserver.logroll.errors.tolerated</name>
<value>2</value>
<description>最大能承受的日志轮转时WAL Writer关闭失败次数</description>
</property>


<property>
<name>hbase.regionserver.logroll.period</name>
<value>3600000</value>
<description>多长时间LogRoller会强制进行日志轮转，默认1小时</description>
</property>


<property>
<name>hbase.regionserver.optionallogflushinterval</name>
<value>1000</value>
<description>多长时间LogSyncer会将HLog持久化到HDFS，默认1秒</description>
</property>


<property>
<name>hbase.regionserver.hlog.splitlog.writer.threads</name>
<value>3</value>
<description>日志划分启动写线程数，默认3</description>
</property>


<property>
<name>hbase.hlog.split.skip.errors</name>
<value>true</value>
</property>


<property>
<name>hbase.regionserver.hlog.blocksize</name>
<value>67108864</value>
<description>HLog写入到HDFS block大小，默认设置为文件系统block大小</description>
</property>


<property>
<name>hbase.regionserver.logroll.multiplier</name>
<value>0.95</value>
<description>HLog当达到blocksize的百分比多大时，将日志轮转</description>
</property>


<property>
<name>hbase.regionserver.maxlogs</name>
<value>32</value>
<description>WAL最大值由这个和blocksize乘积决定，超过将会触发memstore flush，最好这个值稍微大于
                     hbase.regionserver.global.memstore.lowerLimit * HBASE_HEAPSIZE，防止flush雪崩
        </description>
</property>


<property>
<name>hbase.regionserver.hlog.enabled</name>
<value>true</value>
<description>是否关闭写WAL</description>
</property>


<property>
<name>hbase.regionserver.hlog.splitlog.buffersize</name>
<value>128*1024*1024</value>
<description>Split过程中内存缓存Entries大小</description>
</property>


<property>
<name>hbase.master.logcleaner.ttl</name>
<value>600000</value>
<description>HLog存在于.oldlogs文件夹的最长时间，超过了会被master删除，默认10分钟</description>
</property>


<property>
<name>hbase.splitlog.report.interval.loglines</name>
<value>1024</value>
</property>


<property>
<name>hbase.splitlog.report.period</name>
<value>150000</value>
</property>




<property>
<name>hbase.splitlog.report.openedfiles</name>
<value>3</value>
</property>


<property>
<name>hbase.regionserver.hlog.lowreplication.rolllimit</name>
<value>5</value>
</property>


<property>
<name>hbase.regionserver.hlog.reader.impl</name>
<value>org.apache.hadoop.hbase.regionserver.wal.SequenceFileLogReader</value>
</property>


<property>
<name>hbase.master.logcleaner.plugins</name>
<value>org.apache.hadoop.hbase.master.cleaner.TimeToLiveLogCleaner,org.apache.hadoop.hbase.replication.master.ReplicationLogCleaner</value>
<description>放在前面的cleaner先执行，后面的后执行</description>
</property>


<property>
<name>hbase.regionserver.hlog.writer.impl</name>
<value>org.apache.hadoop.hbase.regionserver.wal.SequenceFileLogWriter</value>
</property>


<property>
<name>hbase.regionserver.hlog.keyclass</name>
<value>org.apache.hadoop.hbase.regionserver.wal.HLogKey</value>

</property>

numPutsWithoutWAL
dataInMemoryWithoutWAL
slowHLogAppendCount
slowHLogAppendTime
rollHLogWriterNumOps
rollHLogWriterAvgTime
rollHLogWriterMinTime
rollHLogWriterMaxTime
slowHLogAppendTimeNumOps
slowHLogAppendTimeAvgTime
slowHLogAppendTimeMinTime
slowHLogAppendTimeMaxTime