13.2. Running Volume Top Command

Red Hat Storage Volume Top command allows you to view the glusterFS bricks’ performance metrics like read, write, file open calls, file read calls, file write calls, directory open calls, and directory real calls. The Top command displays up to 100 results.
This section describes how to run and view the results for the following Top commands:

13.2.1. Viewing Open File Descriptor Count and Maximum File Descriptor Count

You can view current open file descriptor count and the list of files that are currently being accessed on the brick . It also displays the maximum open file descriptor count of files that are currently open and the count of maximum number of files opened at any given point of time, since the servers are up and running. If the brick name is not specified, then the open file descriptor metrics of all the bricks belonging to the volume is displayed.
To view open file descriptor count and maximum file descriptor count:
  • View open file descriptor count and maximum file descriptor count using the following command:
    # gluster volume top VOLNAME open [nfs | brick BRICK-NAME] [list-cnt cnt]
    For example, to view open file descriptor count and maximum file descriptor count on brick server:/export of test-volume and list top 10 open calls: 
    # gluster volume top test-volume open brick server:/export/  list-cnt 10 
Brick: server:/export/dir1
Current open fd's: 34 Max open fd's: 209
             ==========Open file stats========

open            file name
call count     

2               /clients/client0/~dmtmp/PARADOX/
                COURSES.DB

11              /clients/client0/~dmtmp/PARADOX/
                ENROLL.DB

11              /clients/client0/~dmtmp/PARADOX/
                STUDENTS.DB

10              /clients/client0/~dmtmp/PWRPNT/
                TIPS.PPT

10              /clients/client0/~dmtmp/PWRPNT/
                PCBENCHM.PPT

9               /clients/client7/~dmtmp/PARADOX/
                STUDENTS.DB

9               /clients/client1/~dmtmp/PARADOX/
                STUDENTS.DB

9               /clients/client2/~dmtmp/PARADOX/
                STUDENTS.DB

9               /clients/client0/~dmtmp/PARADOX/
                STUDENTS.DB

9               /clients/client8/~dmtmp/PARADOX/
                STUDENTS.DB