Re: [RESEND RFC PATCH v2] nvme-pci: add adaptive interrupt polling
Keith Busch <[email protected]>
| Newsgroups | org.infradead.lists.linux-nvme,org.kernel.vger.linux-kernel |
|---|---|
| Message-ID | <an-TwefeWQTSM1ZH@kbusch-mbp> |
On Thu, Aug 13, 2026 at 09:15:31AM +0530, Anuj Gupta wrote: > > I also had a similar assesment on DIM. Emperically, with Keith's POC > interrupts per IO drop from ~1.0 to ~0.29 but with a small performance > regression (572K -> 557K IOPS). With your original approach they drop to > ~0.03 with a 23% performance gain. The DIM machinery overhead maybe > outweighing the partial interrupt reduction. I may ultimately adandon this suggestion, but it looks like a major factor in performance loss was from using IRQ_WAKE_THREAD with sleep cycles instead of the softirq hrtimer. Just changing that is getting me back to performance parity, but since it's not any better, perhaps the hill climb is a worse algorithm than trying to reason out the delayed poll time directly.