[Ocfs2-users] frozen ocfs2 filesystem under heavy webserver load

[Stephan Hendl]

Hi,

I use a cluster of 4 nodes with ocfs2 as a webserver cluster. During a stresstest it occurs after a couple of minutes that the webserverprocesses are ideling but the system load is extremely high (abou 150...200) where the waits are very low. After that I cannot interrupt the webserver processes anymore and in some directories a "ls -ls" comes not back - so it seems that the file system has a problem. Only a reset of the server solves the problem ;-((

In the debug mode I can find the following lines as an example:

Lockres: D00000000000000000ccda0fcc1c07e  Mode: Exclusive
Flags: Initialized Attached
RO Holders: 0  EX Holders: 0
Pending Action: None  Pending Unlock Action: None
Requested Mode: Exclusive  Blocking Mode: Invalid

Lockres: M00000000000000000ccda0fcc1c07e  Mode: Exclusive
Flags: Initialized Attached
RO Holders: 0  EX Holders: 0
Pending Action: None  Pending Unlock Action: None
Requested Mode: Exclusive  Blocking Mode: Invalid

Lockres: D00000000000000000ccd9ffcc1c07d  Mode: Exclusive
Flags: Initialized Attached
RO Holders: 0  EX Holders: 0
Pending Action: None  Pending Unlock Action: None
Requested Mode: Exclusive  Blocking Mode: Invalid

Lockres: M00000000000000000ccd9ffcc1c07d  Mode: Exclusive
Flags: Initialized Attached
RO Holders: 0  EX Holders: 0
Pending Action: None  Pending Unlock Action: None
Requested Mode: Exclusive  Blocking Mode: Invalid

Could it be that two servers like to write to the same file and under heavy load the clusterd processes cannot handle this?

Regards und thanks,
Stephan
-- 

Dr. Stephan Hendl
Systemmanagement
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