Re: [linus:master] [block] e70c301fae: stress-ng.aiol.ops_per_sec 49.6% regression

From: Niklas Cassel
Date: Thu Jan 02 2025 - 04:49:57 EST


Hello Oliver, Christoph,

On Tue, Dec 17, 2024 at 07:56:14AM +0100, Christoph Hellwig wrote:
> On Tue, Dec 17, 2024 at 02:55:23PM +0800, Oliver Sang wrote:
> > from below information, it seems an 'ahci' to me. but since I have limited
> > knowledge about storage driver, maybe I'm wrong. if you want more information,
> > please let us know. thanks a lot!
>
> Yes, this looks like ahci. Thanks a lot!

Did this ever get resolved?

I haven't seen a patch that seems to address this.

AHCI (ata_scsi_queuecmd()) only issues a single command, so if there is any
reordering when issuing a batch of commands, my guess is that the problem
also affects SCSI / the problem is in upper layers above AHCI, i.e. SCSI lib
or block layer.


Kind regards,
Niklas