Lists configuration values for the MapR cluster.
Configuration Fields
The following fields are configurable.
cldb.balancer.disk.max.switches.in.nodes.percentage
- Default Value: 10
- The maximum number of containers that can be balanced in parallel by the disk
balancer. The value is a percentage of the number of nodes in the system.
cldb.disk.balancer.enable
- Default Value: 1 (Disk Balancer is enabled)
- Enables (1) or disables (0) the Disk Balancer.
cldb.balancer.disk.sleep.interval.sec
- Default Value: 120
- The sleep interval (in seconds) between two successive runs of the Disk Balancer.
cldb.balancer.disk.threshold.percentage
- Default Value: 70
- Percentage of used space that causes containers in a storage pool to be distributed
across other less used storage pools.
cldb.balancer.logging
- Default Value: 0
- Disables (0) or enables (1) the logging of messages in the Disk Balancer and Role
Balancer.
cldb.balancer.role.max.switches.in.nodes.percentage
- Default Value: 10
- The percentage (of the number of nodes in the system) to use to determine the maximum
number of containers whose roles (Masters and Tails) are balanced in parallel by the
Role Balancer.
For example, suppose there are 500 nodes and the value of this
parameter is 10(%). The number of containers whose roles are balanced in parallel is
(10/100)*500=50.
cldb.balancer.role.paused
- Default Value: 1
- Enables (0) or Disables (1) the Role Balancer.
cldb.balancer.role.sleep.interval.sec
- Default Value: 900
- The sleep interval (in seconds) between two successive runs of the Role Balancer.
cldb.balancer.startup.interval.sec
- Default Value: 1800
- The initial startup delay (in seconds) of the Role Balancer for existing
clusters.
cldb.cluster.almost.full.percentage
- Default Value: 90
- The percentage at which the
CLUSTER_ALARM_CLUSTER_ALMOST_FULL
alarm is triggered.
cldb.container.alloc.selector.algo
- Default Value: 0
- The allocation algorithm to use when creating new containers. The value can be one of:
- 0 - indicates Round Robin algorithm if the number of nodes is less than or equal
to 100, Randomized algorithm otherwise.
- 1 - indicates Round Robin algorithm. If selected, containers are allocated across
nodes in a topology in a round robin fashion.
- 2 - indicates Randomized algorithm. If selected, containers are allocated across
nodes in a randomized way.
cldb.container.assign.buffer.sizemb
- Default Value: 1024
- The size of the container (in MB) that should be used as a buffer. When allocating a
new container, this size is deducted from the maximum container
size.
NOTE When you modify the value of
cldb.container.sizemb
, check and update the value of
cldb.container.assign.buffer.sizemb
to prevent new containers from
being created when existing containers are not full.
cldb.container.create.diskfull.threshold
- Default Value: 85
- The percentage of space on a file server to use to classify the file server as
full.
cldb.container.sizemb
- Default Value: 32768
-
The maximum size for containers (in MB). This is a soft limit.
NOTE When cldb.container.sizemb
value is modified,
check and update the value of cldb.container.assign.buffer.sizemb
to
prevent new containers from being created when existing containers are not
full.
cldb.default.chunk.sizemb
- Default Value: 256
- The size of each chunk (in MB) that make up a file in the MapR filesystem.
cldb.default.volume.topology
- Default Value: /data
- The default topology for new volumes.
cldb.dialhome.metrics.file.rotation.period
- Default Value: 365
- The retention period of the files (in days) that is used to record Dialhome metrics.
Files that are past their retention period are automatically deleted.
cldb.disable.alarm.history
- Default Value: 0 (false)
- Set this to
1
(true) to disable CLDB alarm history, as tracking and
fetching the alarm history can degrade the performance of CLDB on large clusters.
cldb.fs.mark.rereplicate.sec
- Default Value: 3600
- The number of seconds that a node can fail to heartbeat before it is considered dead.
Once a node is considered dead, the CLDB re-replicates any data contained on the
node.
cldb.fs.reregistration.wait.time
- Default Value: 15
- The amount of time (in minutes) to wait before checking for inactive nodes.
NOTE Reduce the value to raise the
No Heartbeat Alarm without
delay, after CLDB failover. To avoid spurious alarms, do not reduce this value below 5
(minutes).
cldb.log.fileserver.timeskew.interval.mins
- Default Value: 60
- The frequency (in minutes) at which CLDB should log messages about the time skew on
the file server.
cldb.max.parallel.resyncs.star
- Default Value: 3
- The number of container replicas that can resync in parallel from the source for
low-latency (star-replicated) volumes.
cldb.mfs.heartbeat.timeout.multiple
- Default Value: 10
- Specifies a multiple heartbeat timeout. For small clusters, the heartbeat interval is
1 second and the multiple is 10 by default, which makes the heartbeat timeout 10
seconds.
cldb.min.fileservers
- Default Value: 1
- The number of file servers hosting the CLDB volume that is required for the master
CLDB to complete the bootstrap process.
cldb.replication.manager.critical.paused
- Default Value: 0
- Disables (0) or enables (1) the processing of critically under-replicated containers.
If enabled, the critically under-replicated containers are processed on a priority basis
to increase the number of copies.
cldb.replication.manager.max.resyncs.in.nodes.percentage
- Default Value: 1200
- The number of containers that can be replicated in parallel, expressed as a percentage
of the number of active nodes. If the value is 1200, the number of containers that can
be replicated is 12 times the number of active nodes.
cldb.replication.manager.over.paused
- Default Value: 0
- Disables (0) or enables (1) the processing of over-replicated containers.
Over-replicated containers are processed to delete extra copies, which is when the
number of copies is more than the desired replication factor.
cldb.replication.manager.start.mins
- Default Value: 15
- The delay (in minutes) between CLDB startup and replication manager startup, to allow
all nodes to register and heartbeat.
cldb.replication.max.in.transit.containers.per.sp
- Default Value: 4
- The maximum number of containers that can be in transit on a storage pool (SP).
Containers that serve either as the source or destination of a resync operation are
considered as being in ‘transit’.
cldb.replication.sleep.interval.sec
- Default Value: 15
- The sleep duration (in seconds) between consecutive runs of the Replication
Manager.
cldb.replication.tablescan.interval.sec
- Default Value: 120
- The sleep duration (in seconds) between consecutive runs of the Replication Scanner.
While the Replication Scanner classifies containers into different buckets, the Manager
thread either replicates or removes additional copies.
cldb.rm.wait.rack.violated.fork.copy.mins
- Default Value: 720
- The buffer time (in minutes) after which all container copies found on the same rack
are fixed.
cldb.rm.wait.fork.on.same.rack.mins
- Default Value: 180
- The time (in minutes) to defer creating containers on the same rack, for critically
under-replicated containers, if there are at least two copies of the containers.
cldb.security.user.ticket.duration.seconds
- Default Value: 1209600
- The length of time (in seconds) before the user ticket (generated using the
maprlogin password
command) expires.
cldb.security.user.ticket.max.duration.seconds
- Default Value: 2592000
- The maximum amount of time (in seconds) allowed for the user ticket (generated using
the
maprlogin password
command).
cldb.security.user.ticket.renew.duration.seconds
- Default Value: 2592000
- The length of time (in seconds) to renew the user ticket (generated using the
maprlogin password
command).
cldb.security.user.ticket.renew.max.duration.seconds
- Default Value: 7776000
- The maximum duration allowed for a user ticket (generated using
maprlogin password
command)
renewal.
cldb.topology.almost.full.percentage
- Default Value: 90
- The threshold percentage that is used to raise alarms when the used space on the
nodes of a topology exceed a certain percentage of total space.
cldb.volume.epoch
- Default Value: Not Applicable
- The starting epoch of a new Container. Epoch is used internally in the selection of
the master container.
cldb.volumes.namespace.default.min.replication
- Default Value: 2
- The minimum replication factor for the name container. Containers with fewer copies
than this value are replicated on a priority basis.
-
cldb.volumes.namespace.default.replication
- Default Value: 3
- The desired replication factor for the name container.
mapr.fs.nocompression
- Default Value: "bz2,gz,tgz,tbz2, zip,z,Z,mp3,jpg, jpeg,mpg,mpeg,avi,
gif,png,lzo,jar"
- The file types that should not be compressed. See File Extensions of Compressed Files.
mapr.fs.permissions.supergroup
- Default Value: root
- The super group of the MapR filesystem layer.
mapr.fs.permissions.superuser
- Default Value: mapr
- The super user of the MapR filesystem layer.
mapr.targetversion
- Default Value: Not Applicable
- The configuration variable to set the current version of the MapR distribution. Failing to set this
variable on an upgrade causes alarms to be missed when all the nodes in a cluster are
not at the same version of the software.
mfs.db.parallel.copyregions
- Default Value: Not Applicable
- The number of parallel copy regions per MFS instance. Setting this field to a larger
value increases the parallelism for data transfers during index updates, CDC
propagation, and table replication. A larger value increases the transfer rate and
reduces the initial synchronization time, but uses more system resources. The latter may
impact the response time and performance of applications that read data from the same
nodes.
mfs.high.memory.alarm.threshold
- Default Value: 110 (percentage of allocated memory)
- On initialization, the MapR filesystem is allocated a certain amount of memory. There is some
additional headroom that can be used if the MapR filesystem is under memory pressure. However, if
the MapR filesystem
exceeds the high memory threshold (default 10% over the allocated memory, that is 110%),
the High FileServer Memory Alarm is raised. This threshold can be 8%
to 30% over the allocated memory (that is 108% to 130%) .
mfs.feature.db.json.support
- Default Value:
- 1 for new MapR
installations
- 0 for upgraded MapR installations
- Disables (0) or enables (1) MapR streams and support in MapR Database for
JSON documents and tables.
mfs.feature.devicefile.support
- Default Value: 1
- Disables (0) or enables (1) usage of Named Pipes over NFS.
pernode.numcntrs.alarm.thr
- Default Value: 50000
- The maximum number of Read/Write (RW) containers on each node beyond which performance
may not be optimal. The optimal number for RW and snapshot containers combined is 10
times the value of this parameter.