[LU-7218] Client fails to obtain grant: ofd_grant()) fs2test-OST0003: client xxx requesting > 2GB grant 2147483648

Duplicate — Mon, 27 May 2019 14:53:57 +0000

The problem has been detected on Lustre 2.5.3.90.

The application running on the client is failing msync() operation with a SIGBUS signal. Additionally, read/write Posix IO performance is quite low.

The issue comes from an invalid setting of max_dirty_mb tunable value to 2048. After some time the client consumes all its grants and the OSS log the following error message.

1441296045 2015 Sep 3 18:00:45 valx7 kern err kernel LustreError: 16623:0:(ofd_grant.c:607:ofd_grant()) fs2test-OST0003: client fa81e2f5-d6fc-f980-5a79-f76c8a08cec8/ffff880629792c00 requesting > 2GB grant 2147483648

Indeed the max_dirty_mb value should only be set to a value strictly lower than 2GB.

I will post a patch that fixes osc_max_dirty_mb_seq_write() routine to prevent setting the value to 2048.

Whamcloud Community JIRA

[LU-7218] Client fails to obtain grant: ofd_grant()) fs2test-OST0003: client xxx requesting > 2GB grant 2147483648