21.2. Retrieving File Path from the Gluster Volume The heal info command lists the GFIDs of the files that needs to be healed. If you want to find the path of the files associated with the GFIDs, use the getfattr utility. The getfattr utility enables you to locate a file residing on a gluster volume brick. You can retrieve the path of a file even if the filename is unknown. 21.2.1. Retrieving Known File Name To retrieve a file path when the file name is known, execute the following command in the Fuse mount directory: Where, path_to_fuse_mount: The fuse mount where the gluster volume is mounted. filename: The name of the file for which the path information is to be retrieved. For example: The command output displays the brick pathinfo under the <POSIX> tag. In this example output, two paths are displayed as the file is replicated twice. 21.2.2. Retrieving Unknown File Name You can retrieve the file path of an unknown file using its gfid string. The gfid string is the hyphenated version of the trusted.gfid attribute. For example, if the gfid is 80b0b1642ea4478ba4cda9f76c1e6efd , then the gfid string will be 80b0b164-2ea4-478b-a4cd-a9f76c1e6efd . Note To obtain the gfid of a file, run the following command: 21.2.3. Retrieving File Path using gfid String To retrieve the file path using the gfid string, follow these steps: Fuse mount the volume with the aux-gfid option enabled. Where, path_to_fuse_mount: The fuse mount where the gluster volume is mounted. For example: After mounting the volume, execute the following command Where, path_to_fuse_mount: The fuse mount where the gluster volume is mounted. GFID string: The GFID string. For example: The command output displays the brick pathinfo under the <POSIX> tag. In this example output, two paths are displayed as the file is replicated twice. 21.2.4. Controlling Self-heal for Dispersed Volumes For dispersed volumes, when a node with multiple bricks goes offline and comes back online, self-heal daemon starts healing the bricks. This self-heal can lead to high CPU usage in case of large amounts of data and can affect the ongoing I/O operations, thus, decreasing storage efficiency. To control the CPU and memory usage of the self-heal daemon, follow these steps: Navigate to the scripts folder using the following command: Determine the PID of the self-heal daemon using the following command: The output will be in the following format: In this output, 1565 represents the PID of the selfheald service. Execute the control-cpu-load script using the following command: When the system prompts for the following input, type the PID of the self-heal daemon acquired from the step and press Enter : When the system prompts for the following input, type y and press Enter : In this example, 1565 represents the PID of the selfheald service. The PID of the selfheald service can vary from system to system. When the system prompts for the following input, enter the required quota value to be assigned to the self-heal daemon and press Enter : In this example, the quota value for the self-heal daemon is set as 25 . Note The recommended quota value for a self-heal daemon is 25. However, the quota value can be set by the user on a run-time basis. The system prompts the following notification once the quota value is successfully set: To check the CPU usage for the self-heal daemon, execute the top command. Important Perform this procedure every time the daemon is restarted with the new daemon PID.

Commands:
getfattr -n trusted.glusterfs.pathinfo -e text <path_to_fuse_mount/filename>
getfattr -n trusted.glusterfs.pathinfo -e text /mnt/fuse_mnt/File1 getfattr: Removing leading '/' from absolute path names file: mnt/fuse_mnt/File1 trusted.glusterfs.pathinfo="(<DISTRIBUTE:testvol-dht> (<REPLICATE:testvol-replicate-0> <POSIX(/rhgs/brick1):tuxpad:/rhgs/brick1/File1> <POSIX(/rhgs/brick2):tuxpad:/rhgs/brick2/File1>))"
getfattr -d -m. -e hex /path/to/file/on/the/brick
mount -t glusterfs -o aux-gfid-mount hostname:volume-name <path_to_fuse_mnt>
mount -t glusterfs -o aux-gfid-mount 127.0.0.2:testvol /mnt/aux_mount
getfattr -n trusted.glusterfs.pathinfo -e text <path-to-fuse-mnt>/.gfid/<GFID string>
getfattr -n trusted.glusterfs.pathinfo -e text /mnt/aux_mount/.gfid/80b0b164-2ea4-478b-a4cd-a9f76c1e6efd getfattr: Removing leading '/' from absolute path names file: mnt/aux_mount/.gfid/80b0b164-2ea4-478b-a4cd-a9f76c1e6efd trusted.glusterfs.pathinfo="(<DISTRIBUTE:testvol-dht> (<REPLICATE:testvol-replicate-0> <POSIX(/rhgs/brick2):tuxpad:/rhgs/brick2/File1> <POSIX(/rhgs/brick1):tuxpad:/rhgs/brick1/File1>))
cd /usr/share/glusterfs/scripts
ps -aef | grep glustershd
root 1565 1 0 Feb05 ? 00:09:17 /usr/sbin/glusterfs -s localhost --volfile-id gluster/glustershd -p /var/run/gluster/glustershd/glustershd.pid -l /var/log/glusterfs/glustershd.log -S /var/run/gluster/ed49b959a0dc9b2185913084e3b2b339.socket --xlator-option *replicate*.node-uuid=13dbfa1e-ebbf-4cee-a1ac-ca6763903c55 root 16766 14420 0 19:00 pts/0 00:00:00 grep --color=auto glustershd
sh control-cpu-load.sh
sh control-cpu-load.sh Enter gluster daemon pid for which you want to control CPU. 1565
If you want to continue the script to attach 1565 with new cgroup_gluster_1565 cgroup Press (y/n)?
Creating child cgroup directory 'cgroup_gluster_1565 cgroup' for glustershd.service. Enter quota value in range [10,100]: 25
Entered quota value is 25 Setting 25000 to cpu.cfs_quota_us for gluster_cgroup. Tasks are attached successfully specific to 1565 to cgroup_gluster_1565.