Usability

Known issues with usability.

  • CDSW user interface (UI) and other pages might be slow due to DNS settings and short service name. You can test if the UI slowness is caused by the DNS settings by running the following two commands:
    
    time dig feature-flags. default.svc.cluster.local time 
    dig feature-flags.default 

    If the second command returns noticeably slower results, the DNS issues are causing a slowdown.

    Workaround:
    • Reduce the DNS request timeout in your DNS server.

      or

      1. Login to the CDSW master node and note the tgz file name.
        cd /opt/cloudera/parcels/CDSW/config/internal 
        ls cdsw-app-*.tgz
      2. Create a directory called /tmp/cdsw-app.
        mkdir /tmp/cdsw-app
      3. Copy the tgz file to /tmp/cdsw-app.
        cp cdsw-app-*.tgz /tmp/cdsw-app
      4. Navigate to the tmp/cdsw-app directory:
        cd /tmp/cdsw-app
      5. Zip the tgz file:
        gunzip -cvf cdsw-app-*.tgz | tar -xvf -
      6. Navigate to the /tmp/cdsw-app/cdsw-app/templates directory.
        cd /tmp/cdsw-app/cdsw-app/templates
      7. Using a text editor, open the _helpers.tpl file.
        vi _helpers.tpl
      8. Search for dns-ndota-1.
        {{- define "dns-ndots-1" }}
        dnsConfig:
          options:
          - name: ndots
            value: "1"
        {{- end }}
        
      9. Change the entry to the following:
        {{- define "dns-ndots-1" }}
        dnsConfig:
          options:
          - name: ndots
            value: "1"
          - name: timeout
            value: "1"
        {{- end }}
        
      10. Navigate to /tmp.cdsw-app.
        cd /tmp/cdsw-app
      11. Move cdsw-ap.2.0 mv cdsw-app-2.0.0.29262642.tgz to cdsw-app-2.0.0.29262642_backup.tgz:
        mv cdsw-app-2.0.0.29262642.tgz cdsw-app-2.0.0.29262642_backup.tgz
      12. Tar -czf cdsw-app-2.0.0.29262642.tgz cdsw-app.
        tar -czf cdsw-app-2.0.0.29262642.tgz cdsw-app
      13. Remove /opt/cloudera/parcels/CDSW/config/internal/cdsw-app-2.0.0.29262642.tgz.
        rm 
        /opt/cloudera/parcels/CDSW/config/internal/cdsw-app-2.0.0.29262642.tgz
        rm: remove regular file 
        '/opt/cloudera/parcels/CDSW/config/internal/cdsw-app-2.0.0.29262642.tgz'? y
        
      14. Copy cdsw-app-2.0.0.29262642.tgz to /opt/cloudera/parcels/CDSW/config/internal/.
        cp cdsw-app-2.0.0.29262642.tgz /opt/cloudera/parcels/CDSW/config/internal/
      15. Confirm the tgz file is in the directory:
        ls /opt/cloudera/parcels/CDSW/config/internal/cdsw-app-2.0.0.29262642.tgz
      16. Restart CDSW.
      17. Verify the /etc/resolv/conf file contains the timeout configuration:
        cat /etc/resolv.conf
        nameserver 100.77.0.10
        search default.svc.cluster.local svc.cluster.local cluster.local cc-os.cloudera.com
        options ndots:1 timeout:1

      Cloudera Bug: DNS-22673

  • An application can become stuck with the status 'starting' and the user might not be able to find the 'restart' or 'delete' action button.This could be caused by a failure in the selected application script.The exact errors can be found in the logs of the application in the individual description page.

    Workaround: Stop the application from the UI and then Restart the application once the issue in the script is addressed.

  • The Options tab on the Project Settings page is now only viewable to the Administrator. This is because the Private and Team visibility options on the Options page are only viewable by the Administrator.
  • Environment variables with the dollar ($) character are not parsed correctly by CDSW. For example, if you set PASSWORD="pass$123" in the project environment variables, and then try to read it using the echo command, you see the following output: pass23

    Workaround: Use one of the following commands to print the $ sign:
    echo 24 | xxd -r -p
    or
    echo JAo= | base64 -d
    Insert the value of the environment variable by wrapping it in the command substitution using $() or ``. For example, if you want to set the environment variable to ABC$123, specify:
    ABC$(echo 24 | xxd -r -p)123
    or
    ABC`echo 24 | xxd -r -p`123
  • In some cases, the application switcher (grid icon) does not show any other applications, such as Hue or Ranger.

    Cloudera Bug: DSE-865

  • Scala sessions do not respond when running large scripts (longer than 100 lines) in the Workbench editor.

    Workaround 1:

    Run the script in manually-selected chunks. For example, highlight the first 50 lines and select Run > Run Line(s).

    Workaround 2:

    Restructure your code by moving content into imported functions so as to bring the size down to under 100 lines.

  • The R engine is unable to display multi-byte characters in plots. Examples of multi-byte characters include languages such as Korean, Japanese, and Chinese.

    Workaround: Use the showtext R package to support more fonts and characters. For example, to display Korean characters:
    install.packages('showtext')
    library(showtext)
    font_add_google("Noto Sans KR", "noto")
    showtext_auto()

    Cloudera Bug: DSE-7308

  • In a scenario where 100s of users are logged in and creating processes, the nproc and nofile limits of the system may be reached. Use ulimits or other methods to increase the maximum number of processes and open files that can be created by a user on the system.

  • When rebooting, Cloudera Data Science Workbench hosts can take a significant amount of time (about 30 minutes) to become ready.

  • Long-running operations such as fork and clone can time out when projects are large or connections outlast the HTTP timeouts of reverse proxies.

  • The Scala kernel does not support auto-complete features in the editor.

  • Scala and R code can sometimes indent incorrectly in the workbench editor.

    Cloudera Bug: DSE-1218