On 10/09/2013 09:43 AM, Ren Mingxin wrote:
The former minimum valid value of 'eh_deadline' is 1s, which means the earliest occasion to shorten EH is 1 second later since a command is failed or timed out. But if we want to skip EH steps ASAP, we have to wait until the first EH step is finished. If the duration of the first EH step is long, this waiting time is excruciating. So, it is necessary to accept 0 as the minimum valid value for 'eh_deadline'. According to my test, with Hannes' patchset 'New EH command timeout handler' as well, the minimum IO time is improved from 73s (eh_deadline = 1) to 43s(eh_deadline = 0) when commands are timed out by disabling RSCN and target port. Another thing: scsi_finish_command() should be invoked if scsi_eh_scmd_add() is returned on failure - let EH finish those commands.
D'accord. Looks like a valid case. I'll be merging it to my original patchset, seeing that James _still_ hasn't responded to it, let alone merged it. Sigh. Cheers, Hannes -- Dr. Hannes Reinecke zSeries & Storage hare@xxxxxxx +49 911 74053 688 SUSE LINUX Products GmbH, Maxfeldstr. 5, 90409 Nürnberg GF: J. Hawn, J. Guild, F. Imendörffer, HRB 16746 (AG Nürnberg) -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
