Re: [PATCH] nvme-pci: add adaptive interrupt polling
From: Christoph Hellwig
Date: Wed Aug 19 2026 - 01:25:31 EST
On Tue, Aug 18, 2026 at 11:53:55AM +0800, changfengnan wrote:
> 1. Regarding the NVME_ADAPTIVE_POLL_PERIOD_NS parameter, is it necessary to make it a configurable setting? Perhaps Gen6 SSDs require a smaller value? I currently do not have a testing environment for this, but the default value of 10 us appears to be sufficient for Gen4 and Gen5.
The most important thing to consider in the short term is not the fastest
possible devices, but the worst. I.e. consider what this does on really
crappy older cusomer drives, as that is probably the biggest install base
using the Linux nvme driver.
> 2. Should MSI be supported? I do not have a similar environment, so I am unsure how it would perform in such scenarios.
Or legacy interrupts :) I don't think we have to support them as long
as we cleanly disable the feature.
> 3. Should it be enabled by default? Although current tests show only a minor performance hit, I still lean toward disabling it by default and waiting to gather more test feedback.
I think it should eventually enabled by default, but I'd also be happy
to merge it fist and then flip the bit later.