Just as in Hadoop where you add site-specific HDFS configuration to the
hdfs-site.xml file, for HBase, site specific customizations go into the file conf/hbase-site.xml.
Not all configuration options make it out to
hbase-default.xml. Configuration that it is thought rare anyone would change can exist only in code; the only way to turn up such configurations is via a reading of the source code itself.
Currently, changes here will require a cluster restart for HBase to notice the change.
HBase Default Configuration
The documentation below is generated using the default hbase configuration file,
hbase-default.xml, as source.hbase.rootdir- The directory shared by region servers and into which HBase persists. The URL should be 'fully-qualified' to include the filesystem scheme. For example, to specify the HDFS directory '/hbase' where the HDFS instance's namenode is running at namenode.example.org on port 9000, set this value to: hdfs://namenode.example.org:9000/hbase. By default HBase writes into /tmp. Change this configuration else all data will be lost on machine restart.
Default:file:///tmp/hbase-${user.name}/hbase
hbase.master.port- The port the HBase Master should bind to.
Default:60000
hbase.cluster.distributed- The mode the cluster will be in. Possible values are false for standalone mode and true for distributed mode. If false, startup will run all HBase and ZooKeeper daemons together in the one JVM.
Default:false
hbase.tmp.dir- Temporary directory on the local filesystem. Change this setting to point to a location more permanent than '/tmp' (The '/tmp' directory is often cleared on machine restart).
Default:${java.io.tmpdir}/hbase-${user.name}
hbase.local.dir- Directory on the local filesystem to be used as a local storage.
Default:${hbase.tmp.dir}/local/
hbase.master.info.port- The port for the HBase Master web UI. Set to -1 if you do not want a UI instance run.
Default:60010
hbase.master.info.bindAddress- The bind address for the HBase Master web UI
Default:0.0.0.0
hbase.client.write.buffer- Default size of the HTable clien write buffer in bytes. A bigger buffer takes more memory -- on both the client and server side since server instantiates the passed write buffer to process it -- but a larger buffer size reduces the number of RPCs made. For an estimate of server-side memory-used, evaluate hbase.client.write.buffer * hbase.regionserver.handler.count
Default:2097152
hbase.regionserver.port- The port the HBase RegionServer binds to.
Default:60020 hbase.regionserver.info.port- The port for the HBase RegionServer web UI Set to -1 if you do not want the RegionServer UI to run.
Default:60030
hbase.regionserver.info.port.auto- Whether or not the Master or RegionServer UI should search for a port to bind to. Enables automatic port search if hbase.regionserver.info.port is already in use. Useful for testing, turned off by default.
Default:false
hbase.regionserver.info.bindAddress- The address for the HBase RegionServer web UI
Default:0.0.0.0
hbase.client.pause- General client pause value. Used mostly as value to wait before running a retry of a failed get, region lookup, etc.
Default:1000
hbase.client.retries.number- Maximum retries. Used as maximum for all retryable operations such as fetching of the root region from root region server, getting a cell's value, starting a row update, etc. Default: 10.
Default:10
hbase.bulkload.retries.number- Maximum retries. This is maximum number of iterations to atomic bulk loads are attempted in the face of splitting operations 0 means never give up. Default: 0.
Default:0
hbase.client.scanner.caching- Number of rows that will be fetched when calling next on a scanner if it is not served from (local, client) memory. Higher caching values will enable faster scanners but will eat up more memory and some calls of next may take longer and longer times when the cache is empty. Do not set this value such that the time between invocations is greater than the scanner timeout; i.e. hbase.client.scanner.timeout.period
Default:100
hbase.client.keyvalue.maxsize- Specifies the combined maximum allowed size of a KeyValue instance. This is to set an upper boundary for a single entry saved in a storage file. Since they cannot be split it helps avoiding that a region cannot be split any further because the data is too large. It seems wise to set this to a fraction of the maximum region size. Setting it to zero or less disables the check.
Default:10485760
hbase.client.scanner.timeout.period- Client scanner lease period in milliseconds. Default is 60 seconds.
Default:60000
hbase.regionserver.handler.count- Count of RPC Listener instances spun up on RegionServers. Same property is used by the Master for count of master handlers. Default is 10.
Default:10
hbase.regionserver.msginterval- Interval between messages from the RegionServer to Master in milliseconds.
Default:3000
hbase.regionserver.optionallogflushinterval- Sync the HLog to the HDFS after this interval if it has not accumulated enough entries to trigger a sync. Default 1 second. Units: milliseconds.
Default:1000
hbase.regionserver.regionSplitLimit- Limit for the number of regions after which no more region splitting should take place. This is not a hard limit for the number of regions but acts as a guideline for the regionserver to stop splitting after a certain limit. Default is set to MAX_INT; i.e. do not block splitting.
Default:2147483647
hbase.regionserver.logroll.period- Period at which we will roll the commit log regardless of how many edits it has.
Default:3600000
hbase.regionserver.logroll.errors.tolerated- The number of consecutive WAL close errors we will allow before triggering a server abort. A setting of 0 will cause the region server to abort if closing the current WAL writer fails during log rolling. Even a small value (2 or 3) will allow a region server to ride over transient HDFS errors.
Default:2
hbase.regionserver.hlog.reader.impl- The HLog file reader implementation.
Default:org.apache.hadoop.hbase.regionserver.wal.ProtobufLogReader hbase.regionserver.hlog.writer.impl- The HLog file writer implementation.
Default:org.apache.hadoop.hbase.regionserver.wal.ProtobufLogWriter
hbase.regionserver.nbreservationblocks- The number of resevoir blocks of memory release on OOME so we can cleanup properly before server shutdown.
Default:4
hbase.zookeeper.dns.interface- The name of the Network Interface from which a ZooKeeper server should report its IP address.
Default:default
hbase.zookeeper.dns.nameserver- The host name or IP address of the name server (DNS) which a ZooKeeper server should use to determine the host name used by the master for communication and display purposes.
Default:default
hbase.regionserver.dns.interface- The name of the Network Interface from which a region server should report its IP address.
Default:default
hbase.regionserver.dns.nameserver- The host name or IP address of the name server (DNS) which a region server should use to determine the host name used by the master for communication and display purposes.
Default:default hbase.master.dns.interface- The name of the Network Interface from which a master should report its IP address.
Default:default
hbase.master.dns.nameserver- The host name or IP address of the name server (DNS) which a master should use to determine the host name used for communication and display purposes.
Default:default
hbase.balancer.period- Period at which the region balancer runs in the Master.
Default:300000 hbase.regions.slop- Rebalance if any regionserver has average + (average * slop) regions. Default is 20% slop.
Default:0.2
hbase.master.logcleaner.ttl- Maximum time a HLog can stay in the .oldlogdir directory, after which it will be cleaned by a Master thread.
Default:600000
hbase.master.logcleaner.plugins- A comma-separated list of LogCleanerDelegate invoked by the LogsCleaner service. These WAL/HLog cleaners are called in order, so put the HLog cleaner that prunes the most HLog files in front. To implement your own LogCleanerDelegate, just put it in HBase's classpath and add the fully qualified class name here. Always add the above default log cleaners in the list.
Default:org.apache.hadoop.hbase.master.cleaner.TimeToLiveLogCleaner
hbase.regionserver.global.memstore.upperLimit- Maximum size of all memstores in a region server before new updates are blocked and flushes are forced. Defaults to 40% of heap. Updates are blocked and flushes are forced until size of all memstores in a region server hits hbase.regionserver.global.memstore.lowerLimit.
Default:0.4
hbase.regionserver.global.memstore.lowerLimit- Maximum size of all memstores in a region server before flushes are forced. Defaults to 35% of heap. This value equal to hbase.regionserver.global.memstore.upperLimit causes the minimum possible flushing to occur when updates are blocked due to memstore limiting.
Default:0.35
hbase.server.thread.wakefrequency- Time to sleep in between searches for work (in milliseconds). Used as sleep interval by service threads such as log roller.
Default:10000
hbase.server.versionfile.writeattempts- How many time to retry attempting to write a version file before just aborting. Each attempt is seperated by the hbase.server.thread.wakefrequency milliseconds.
Default:3
hbase.regionserver.optionalcacheflushinterval- Maximum amount of time an edit lives in memory before being automatically flushed. Default 1 hour. Set it to 0 to disable automatic flushing.
Default:3600000
hbase.hregion.memstore.flush.size- Memstore will be flushed to disk if size of the memstore exceeds this number of bytes. Value is checked by a thread that runs every hbase.server.thread.wakefrequency.
Default:134217728
hbase.hregion.preclose.flush.size- If the memstores in a region are this size or larger when we go to close, run a "pre-flush" to clear out memstores before we put up the region closed flag and take the region offline. On close, a flush is run under the close flag to empty memory. During this time the region is offline and we are not taking on any writes. If the memstore content is large, this flush could take a long time to complete. The preflush is meant to clean out the bulk of the memstore before putting up the close flag and taking the region offline so the flush that runs under the close flag has little to do.
Default:5242880
hbase.hregion.memstore.block.multiplier- Block updates if memstore has hbase.hregion.block.memstore time hbase.hregion.flush.size bytes. Useful preventing runaway memstore during spikes in update traffic. Without an upper-bound, memstore fills such that when it flushes the resultant flush files take a long time to compact or split, or worse, we OOME.
Default:2
hbase.hregion.memstore.mslab.enabled- Enables the MemStore-Local Allocation Buffer, a feature which works to prevent heap fragmentation under heavy write loads. This can reduce the frequency of stop-the-world GC pauses on large heaps.
Default:true
hbase.hregion.max.filesize- Maximum HStoreFile size. If any one of a column families' HStoreFiles has grown to exceed this value, the hosting HRegion is split in two. Default: 10G.
Default:10737418240 hbase.hstore.compactionThreshold- If more than this number of HStoreFiles in any one HStore (one HStoreFile is written per flush of memstore) then a compaction is run to rewrite all HStoreFiles files as one. Larger numbers put off compaction but when it runs, it takes longer to complete.
Default:3
hbase.hstore.blockingStoreFiles- If more than this number of StoreFiles in any one Store (one StoreFile is written per flush of MemStore) then updates are blocked for this HRegion until a compaction is completed, or until hbase.hstore.blockingWaitTime has been exceeded.
Default:7
hbase.hstore.blockingWaitTime- The time an HRegion will block updates for after hitting the StoreFile limit defined by hbase.hstore.blockingStoreFiles. After this time has elapsed, the HRegion will stop blocking updates even if a compaction has not been completed. Default: 90 seconds.
Default:90000
hbase.hstore.compaction.max- Max number of HStoreFiles to compact per 'minor' compaction.
Default:10
hbase.hregion.majorcompaction- The time (in miliseconds) between 'major' compactions of all HStoreFiles in a region. Default: 1 day. Set to 0 to disable automated major compactions.
Default:86400000 hbase.storescanner.parallel.seek.enable- Enables StoreFileScanner parallel-seeking in StoreScanner, a feature which can reduce response latency under special conditions.
Default:false
hbase.storescanner.parallel.seek.threads- The default thread pool size if parallel-seeking feature enabled.
Default:10
hbase.mapreduce.hfileoutputformat.blocksize- The mapreduce HFileOutputFormat writes storefiles/hfiles. This is the minimum hfile blocksize to emit. Usually in hbase, writing hfiles, the blocksize is gotten from the table schema (HColumnDescriptor) but in the mapreduce outputformat context, we don't have access to the schema so get blocksize from Configuration. The smaller you make the blocksize, the bigger your index and the less you fetch on a random-access. Set the blocksize down if you have small cells and want faster random-access of individual cells.
Default:65536
hfile.block.cache.size- Percentage of maximum heap (-Xmx setting) to allocate to block cache used by HFile/StoreFile. Default of 0.25 means allocate 25%. Set to 0 to disable but it's not recommended.
Default:0.25 hbase.hash.type- The hashing algorithm for use in HashFunction. Two values are supported now: murmur (MurmurHash) and jenkins (JenkinsHash). Used by bloom filters.
Default:murmur
hfile.block.index.cacheonwrite- This allows to put non-root multi-level index blocks into the block cache at the time the index is being written.
Default:false
hfile.index.block.max.size- When the size of a leaf-level, intermediate-level, or root-level index block in a multi-level block index grows to this size, the block is written out and a new block is started.
Default:131072
hfile.format.version- The HFile format version to use for new files. Set this to 1 to test backwards-compatibility. The default value of this option should be consistent with FixedFileTrailer.MAX_VERSION.
Default:2
io.storefile.bloom.block.size- The size in bytes of a single block ("chunk") of a compound Bloom filter. This size is approximate, because Bloom blocks can only be inserted at data block boundaries, and the number of keys per data block varies.
Default:131072
hfile.block.bloom.cacheonwrite- Enables cache-on-write for inline blocks of a compound Bloom filter.
Default:false hbase.rs.cacheblocksonwrite- Whether an HFile block should be added to the block cache when the block is finished.
Default:false hbase.rpc.server.engine- Implementation of org.apache.hadoop.hbase.ipc.RpcServerEngine to be used for server RPC call marshalling.
Default:org.apache.hadoop.hbase.ipc.ProtobufRpcServerEngine
hbase.ipc.client.tcpnodelay- Set no delay on rpc socket connections.
Default:true
hadoop.policy.file- The policy configuration file used by RPC servers to make authorization decisions on client requests. Only used when HBase security is enabled.
Default:hbase-policy.xml hbase.auth.key.update.interval- The update interval for master key for authentication tokens in servers in milliseconds. Only used when HBase security is enabled.
Default:86400000
hbase.auth.token.max.lifetime- The maximum lifetime in milliseconds after which an authentication token expires. Only used when HBase security is enabled.
Default:604800000
zookeeper.session.timeout- ZooKeeper session timeout. HBase passes this to the zk quorum as suggested maximum time for a session (This setting becomes zookeeper's 'maxSessionTimeout'). "The client sends a requested timeout, the server responds with the timeout that it can give the client. " In milliseconds.
Default:180000
zookeeper.znode.parent- Root ZNode for HBase in ZooKeeper. All of HBase's ZooKeeper files that are configured with a relative path will go under this node. By default, all of HBase's ZooKeeper file path are configured with a relative path, so they will all go under this directory unless changed.
Default:/hbase
zookeeper.znode.rootserver- Path to ZNode holding root region location. This is written by the master and read by clients and region servers. If a relative path is given, the parent folder will be ${zookeeper.znode.parent}. By default, this means the root location is stored at /hbase/root-region-server.
Default:root-region-server zookeeper.znode.acl.parent- Root ZNode for access control lists.
Default:acl
hbase.coprocessor.region.classes- A comma-separated list of Coprocessors that are loaded by default on all tables. For any override coprocessor method, these classes will be called in order. After implementing your own Coprocessor, just put it in HBase's classpath and add the fully qualified class name here. A coprocessor can also be loaded on demand by setting HTableDescriptor.
Default:
hbase.coprocessor.master.classes- A comma-separated list of org.apache.hadoop.hbase.coprocessor.MasterObserver coprocessors that are loaded by default on the active HMaster process. For any implemented coprocessor methods, the listed classes will be called in order. After implementing your own MasterObserver, just put it in HBase's classpath and add the fully qualified class name here.
Default:
hbase.zookeeper.quorum- Comma separated list of servers in the ZooKeeper Quorum. For example, "host1.mydomain.com,host2.mydomain.com,host3.mydomain.com". By default this is set to localhost for local and pseudo-distributed modes of operation. For a fully-distributed setup, this should be set to a full list of ZooKeeper quorum servers. If HBASE_MANAGES_ZK is set in hbase-env.sh this is the list of servers which we will start/stop ZooKeeper on.
Default:localhost
hbase.zookeeper.useMulti- Instructs HBase to make use of ZooKeeper's multi-update functionality. This allows certain ZooKeeper operations to complete more quickly and prevents some issues with rare Replication failure scenarios
IMPORTANT: only set this to true if all ZooKeeper servers in the cluster are on version 3.4+ and will not be downgraded. ZooKeeper versions before 3.4 do not support multi-update and will not fail gracefully if multi-update is invoked (see ZOOKEEPER-1495).
Default:false
hbase.zookeeper.property.initLimit- Property from ZooKeeper's config zoo.cfg. The number of ticks that the initial synchronization phase can take.
Default:10
hbase.zookeeper.property.syncLimit- Property from ZooKeeper's config zoo.cfg. The number of ticks that can pass between sending a request and getting an acknowledgment.
Default:5
hbase.zookeeper.property.dataDir- Property from ZooKeeper's config zoo.cfg. The directory where the snapshot is stored.
Default:${hbase.tmp.dir}/zookeeper
hbase.zookeeper.property.clientPort- Property from ZooKeeper's config zoo.cfg. The port at which the clients will connect.
Default:2181
hbase.zookeeper.property.maxClientCnxns- Property from ZooKeeper's config zoo.cfg. Limit on number of concurrent connections (at the socket level) that a single client, identified by IP address, may make to a single member of the ZooKeeper ensemble. Set high to avoid zk connection issues running standalone and pseudo-distributed.
Default:300
hbase.rest.port- The port for the HBase REST server.
Default:8080
hbase.rest.readonly- Defines the mode the REST server will be started in. Possible values are: false: All HTTP methods are permitted - GET/PUT/POST/DELETE. true: Only the GET method is permitted.
Default:false
hbase.defaults.for.version.skip- Set to true to skip the 'hbase.defaults.for.version' check. Setting this to true can be useful in contexts other than the other side of a maven generation; i.e. running in an ide. You'll want to set this boolean to true to avoid seeing the RuntimException complaint: "hbase-default.xml file seems to be for and old version of HBase (\${hbase.version}), this version is X.X.X-SNAPSHOT"
Default:false
hbase.coprocessor.abortonerror- Set to true to cause the hosting server (master or regionserver) to abort if a coprocessor throws a Throwable object that is not IOException or a subclass of IOException. Setting it to true might be useful in development environments where one wants to terminate the server as soon as possible to simplify coprocessor failure analysis.
Default:false
hbase.online.schema.update.enable- Set true to enable online schema changes. This is an experimental feature. There are known issues modifying table schemas at the same time a region split is happening so your table needs to be quiescent or else you have to be running with splits disabled.
Default:false
hbase.table.lock.enable- Set to true to enable locking the table in zookeeper for schema change operations. Table locking from master prevents concurrent schema modifications to corrupt table state.
Default:true
dfs.support.append- Does HDFS allow appends to files? This is an hdfs config. set in here so the hdfs client will do append support. You must ensure that this config. is true serverside too when running hbase (You will have to restart your cluster after setting it).
Default:true
hbase.thrift.minWorkerThreads- The "core size" of the thread pool. New threads are created on every connection until this many threads are created.
Default:16
hbase.thrift.maxWorkerThreads- The maximum size of the thread pool. When the pending request queue overflows, new threads are created until their number reaches this number. After that, the server starts dropping connections.
Default:1000
hbase.thrift.maxQueuedRequests- The maximum number of pending Thrift connections waiting in the queue. If there are no idle threads in the pool, the server queues requests. Only when the queue overflows, new threads are added, up to hbase.thrift.maxQueuedRequests threads.
Default:1000 hbase.offheapcache.percentage- The amount of off heap space to be allocated towards the experimental off heap cache. If you desire the cache to be disabled, simply set this value to 0.
Default:0 hbase.data.umask.enable- Enable, if true, that file permissions should be assigned to the files written by the regionserver
Default:false
hbase.data.umask- File permissions that should be used to write data files when hbase.data.umask.enable is true
Default:000
hbase.metrics.showTableName- Whether to include the prefix "tbl.tablename" in per-column family metrics. If true, for each metric M, per-cf metrics will be reported for tbl.T.cf.CF.M, if false, per-cf metrics will be aggregated by column-family across tables, and reported for cf.CF.M. In both cases, the aggregated metric M across tables and cfs will be reported.
Default:true hbase.metrics.exposeOperationTimes- Whether to report metrics about time taken performing an operation on the region server. Get, Put, Delete, Increment, and Append can all have their times exposed through Hadoop metrics per CF and per region.
Default:true
hbase.master.hfilecleaner.plugins- A comma-separated list of HFileCleanerDelegate invoked by the HFileCleaner service. These HFiles cleaners are called in order, so put the cleaner that prunes the most files in front. To implement your own HFileCleanerDelegate, just put it in HBase's classpath and add the fully qualified class name here. Always add the above default log cleaners in the list as they will be overwritten in hbase-site.xml.
Default:org.apache.hadoop.hbase.master.cleaner.TimeToLiveHFileCleaner
hbase.regionserver.catalog.timeout- Timeout value for the Catalog Janitor from the regionserver to META.
Default:600000
hbase.master.catalog.timeout- Timeout value for the Catalog Janitor from the master to META.
Default:600000
hbase.config.read.zookeeper.config- Set to true to allow HBaseConfiguration to read the zoo.cfg file for ZooKeeper properties. Switching this to true is not recommended, since the functionality of reading ZK properties from a zoo.cfg file has been deprecated.
Default:false
hbase.snapshot.enabled- Set to true to allow snapshots to be taken / restored / cloned.
Default:true
hbase.rest.threads.max- The maximum number of threads of the REST server thread pool. Threads in the pool are reused to process REST requests. This controls the maximum number of requests processed concurrently. It may help to control the memory used by the REST server to avoid OOM issues. If the thread pool is full, incoming requests will be queued up and wait for some free threads. The default is 100.
Default:100
hbase.rest.threads.min- The minimum number of threads of the REST server thread pool. The thread pool always has at least these number of threads so the REST server is ready to serve incoming requests. The default is 2.
Default:2
hbase.rpc.timeout- This is for the RPC layer to define how long HBase client applications take for a remote call to time out. It uses pings to check connections but will eventually throw a TimeoutException. The default value is 60000ms(60s).
Default:60000
hbase.server.compactchecker.interval.multiplier- The number that determines how often we scan to see if compaction is necessary. Normally, compactions are done after some events (such as memstore flush), but if region didn't receive a lot of writes for some time, or due to different compaction policies, it may be necessary to check it periodically. The interval between checks is hbase.server.compactchecker.interval.multiplier multiplied by hbase.server.thread.wakefrequency.
Default:1000
hbase-env.sh
conf/hbase-env.sh and peruse its content. Each option is fairly well documented. Add your own environment variables here if you want them read by HBase daemons on startup.Changes here will require a cluster restart for HBase to notice the change.
log4j.properties
Changes here will require a cluster restart for HBase to notice the change though log levels can be changed for particular daemons via the HBase UI.
Get Hands-on Training @ BigDataTraining.IN
BigDataTraining.IN - India's Leading BigData Consulting & Training Provider, Request a Quote!
Hadoop & Big Data Training | Development | Consulting | Projects
http://www.bigdatatraining.in/hadoop-training-chennai/
http://www.hadooptrainingchennai.in/hadoop-training-in-chennai/
http://www.bigdatatraining.in/
email : info@bigdatatraining.in
Phone: +91 9789968765, 044-42645495
Hadoop & Big Data Training | Development | Consulting | Projects
http://www.bigdatatraining.in/hadoop-training-chennai/
http://www.hadooptrainingchennai.in/hadoop-training-in-chennai/
http://www.bigdatatraining.in/
email : info@bigdatatraining.in
Phone: +91 9789968765, 044-42645495
No comments:
Post a Comment