I have a very strange problem with db2 commands getting extremely slower. DB2 V11.1 Express-C Centos 7.3
type db2 to bring the interactive command prompt takes about 30 sec to display.
db2licm -l and db2level also takes exact 30 sec to display
db2 list db/node directory commands also take 30 sec to come up with the information.
These things usually have a sub second response times. I do not even need to start the instance. this is just pure db2 commands.
I fixed the issue in a very weird manner. I observed there is no paging, swapping or high CPU or Memory issues on the server. I was really clueless, what is happening. So verified whether libaio is installed. Just was guessing that AIO may be an issue. It is installed and latest version only. After this step, the db2 commands were running super fast. sub second response times on all the commands that have mentioned above.
The Repository Information of Linux Packages were refreshed because of my yum command. After that every thing started working fine.
What I could not understand is that this slowness is only observed in db2 commands and not in File Manager, gedit or Browsers etc.. All Linux Applications run well. Only db2 commands were too slow and updating repository information of OS fixed the issue. Very Very Bizzare and do not know why it happens to me only.