wanpengqian_gmail.com retitled this revision from Set Abort Command Limit (ACL) and Asynchronous Event Request Limit (AERL) values as specfica ton suggested. to bhyve: nvme set Abort Command Limit (ACL) and Asynchronous Event Request Limit (AERL) values as specfication suggested.Aug 25 2022, 5:06 AM

wanpengqian_gmail.com edited the summary of this revision. (Show Details)

chuck added inline comments.Aug 31 2022, 12:55 AM

usr.sbin/bhyve/pci_nvme.c
545	There isn't a limit on the number of concurrent aborts in the implementation. So one arbitrary value is as good as another, but I'd suggest removing the comment.
546	The wording in the specification is: It is recommended that implementations support a minimum of four Asynchronous Event Request Limit commands outstanding simultaneously. Supporting 5 (`aerl = 4`) would meet their recommendation, wouldn't you agree?

wanpengqian_gmail.com added inline comments.Aug 31 2022, 1:34 AM

usr.sbin/bhyve/pci_nvme.c
545	You are right, currently the Abort Command is not processed by the controller. I'd like the value to be more normal as real nvme controllers use the specification recommended value. I will remove the comment later.
546	Yes, a value higher than 4 is totally OK as specification says. but the value of 5 is a little un-normal. I don't know why we pick up this value at first. as 4 is the value that other controllers do as far as my observation.