Re: [PATCH v6 1/4] block: Make fair tag sharing configurable

[Bart Van Assche <bvanassche@acm.org>]

On 1/24/24 01:08, Christoph Hellwig wrote:
> On Tue, Jan 23, 2024 at 07:16:05AM -0800, Bart Van Assche wrote:
>> On 1/23/24 01:13, Christoph Hellwig wrote:
>>> The point is why you think fair sharing is not actually required for
>>> these particular setups only.
>>
>> Do you perhaps want me to move the SCSI host sysfs attribute that controls
>> fair sharing to the /sys/block/${bdev}/queue directory?
> 
> No.  I want an explanation from you why you think your use case is so
> snowflake special that you and just you need to fisable fair sharing.

Hi Christoph,

Would you agree with disabling fair sharing entirely? The use cases that
need fair sharing most are those were different storage types (e.g. hard
disk and SSDs) are connected to the same storage controller. This scenario
often occurs in a cloud computing context. There are better solutions for
cloud computing contexts than fair sharing, e.g. associating different
storage types with different storage controllers. The same approach works
for storage-over-network since storage arrays that have a network connection
usually support to establish multiple connections from a storage initiator
to the storage server.

Thanks,

Bart.