[lustre-discuss] Is there a way to have faster lustre file system checker (lfsck)?

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Hi all, 

I am still new to Lustre, so please let me know if I should send this message to devel-list. 

This week, I tried to run LFSCK over a very small cluster configuration (1 mdt and 3 osts).  In this Lustre, I used about 300K inodes.  It took me about 80 mins to finish a LFSCK run.  And, more importantly, while I am running LFSCK, on both MDT and OSTS, the CPU utilization is 100%, taken by the lfsck thread. 

I understand that lfsck is operating in an online mode, so it is slow.  But, I am wondering is there any way to accelerate this?  Especially if I am allowed to run it offline, for example, during weekly maintenance.

After checking the lfsck kernel logs, I noticed that in the phase2 scanning on OSTs, there is an 30 seconds interval between querying the MDTs.  I am wondering is there any reason to have this 30 seconds interval, and will lfsck on OSTs be faster if we remove such 30 seconds interval?

Thanks,
- Dong