Configuring the MapR POSIX Client
About this task
The default RPC requests configuration can negatively impact performance and memory. To avoid performance and memory issues, configure the number of outstanding RPC requests to the cluster to be 128.
Perform the following steps as the root user on each POSIX client machine:
Procedure
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Issue the following commands to create the sunrpc.conf file under /etc/modprobe.d
with the recommended configuration:
This will enable the configuration to persist after a reboot of the NFS client machine.echo "options sunrpc tcp_slot_table_entries=128" >> /etc/modprobe.d/sunrpc.conf echo "options sunrpc tcp_max_slot_table_entries=128" >> /etc/modprobe.d/sunrpc.conf
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Issue the following echo commands:
This will enable the configuration to take effect after you remount the POSIX client to the MapR cluster.echo 128 > /proc/sys/sunrpc/tcp_slot_table_entries echo 128 > /proc/sys/sunrpc/tcp_max_slot_table_entries
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Remount the POSIX client to the Mapr cluster. For example, the following commands
unmount and mount the NFS assuming that the cluster is mounted at /mapr:
# umount /mapr # mount -o hard,nolock 127.0.0.1:/mapr /mapr
NOTE: Failure to configure this property may result in the following error in /usr/local/mapr-loopbacknfs/log: ERROR nfsserver[38960] fs/nfsd/requesthandle.cc:791 0.0.0.0[0] cannot allocate more OncRpcContexts: [numDropped=2556001] dropping connection from nfsc=10.13.64.225:0CentOS Troubleshooting Tip
After the reboot of the node, if the
/proc/sys/sunrpc
directory not available or if rpcidmapd is not running, start the rpcidmapd service using the following command: service rpcidmapd start