Re: [PATCH] scsi: Allow error handling timeout to be specified

Martin K. Petersen
2013-05-10T14:54:02Z

>>>>> "Baruch" == Baruch Even <baruch@ev-en.org> writes:

Baruch> Actually reducing the timeouts is probably not a good approach
Baruch> since it will cause the host to take a more radical approach
Baruch> without waiting sufficiently for a potential recovery.

Reducing the eh timeout is a requirement in many clustered setups. We've
been shipping a predecessor to this patch in our kernels for a long
time.

Baruch> In addition the more radical error handlings such as host reset
Baruch> will destroy other paths for completely unrelated devices/links,
Baruch> from my experience a host reset is usually not required and the
Baruch> Linux kernel currently reaches to this big hammer too fast.

I'm also working on a patch to add some heuristics to avoid the HBA and
bus resets if I/O is completing successfully on other attached
targets. But that's an orthogonal issue.

--
Martin K. Petersen Oracle Linux Engineering