Re: Report: Performance regression from ib_umem_get on zone device pages

To: Jason Gunthorpe <jgg@xxxxxxxx>
Subject: Re: Report: Performance regression from ib_umem_get on zone device pages
From: jane.chu@xxxxxxxxxx
Date: Wed, 23 Apr 2025 19:55:39 -0700
Cc: logane@xxxxxxxxxxxx, hch@xxxxxx, gregkh@xxxxxxxxxxxxxxxxxxx, willy@xxxxxxxxxxxxx, kch@xxxxxxxxxx, axboe@xxxxxxxxx, linux-kernel@xxxxxxxxxxxxxxx, linux-mm@xxxxxxxxx, linux-pci@xxxxxxxxxxxxxxx, linux-nvme@xxxxxxxxxxxxxxxxxxx, linux-block@xxxxxxxxxxxxxxx
In-reply-to: <20250423232828.GV1213339@ziepe.ca>
References: <fe761ea8-650a-4118-bd53-e1e4408fea9c@oracle.com> <20250423232828.GV1213339@ziepe.ca>
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On 4/23/2025 4:28 PM, Jason Gunthorpe wrote:

IIRC device-dax does could not use folios until 6.15 so I'm assuming
it is not folios even if it is a pmd mapping?

I just looked at 6.15-rc3, device-dax is not using folio. Maybe I'mmissing some upcoming patches?


thanks,
-jane

Follow-Ups:
- Re: Report: Performance regression from ib_umem_get on zone device pages
  - From: jane . chu

References:
- Report: Performance regression from ib_umem_get on zone device pages
  - From: jane . chu
- Re: Report: Performance regression from ib_umem_get on zone device pages
  - From: Jason Gunthorpe