[LU-4768] ost-survey hangs on client 2.4

• Type: Bug
• Resolution: Fixed
• Priority: Minor
• Fix Version/s: Lustre 2.7.0
• Affects Version/s: Lustre 2.4.2
• Environment: mds, oss: lustre 2.4.2 (CentOS 6.5 with lustre patched kernel RPM); client: lustre 2.4.2 (CentOS 6.5 patchless client, lustre iokit 1.4.0.1)

Epic/Theme

test

• Severity: 3
• Assignee: James Nunez (Inactive)
• Reporter: francesco de giorgi

Description

ost-survey on this environment

mds, oss: lustre 2.4.2 (CentOS 6.5 with lustre patched kernel RPM)
client: lustre 2.4.2 (CentOS 6.5 patchless client, lustre iokit 1.4.0.1)

command line: ost-survey -s 100 /lustre

will hang, chewing all the CPU in the attempt to
echo 0 in /proc/fs/lustre/llite/*/max_cached_mb . This is due to the
subroutine cache_off in the ost-survey script.

In a lustre client 2.1.6 the max_cached_mb appears as
a single number

1. cat /proc/fs/lustre/llite/*/max_cached_mb
   18114

but on a 2.4.2 client is different

1. cat /proc/fs/lustre/llite/*/max_cached_mb
   users: 2
   max_cached_mb: 96766
   used_mb: 21806
   unused_mb: 74960
   reclaim_count: 0

So probably the script has not been fixed to work with the new output.

Issue Links

• is related to: LU-5773 obdfilter-survey test 1c: oom occurred on OSS
• is related to: LU-5030 "lctl {get,set}_param" should also check in /sys/fs/{lnet,lustre}