Re: [LSF/MM TOPIC][LSF/MM ATTEND] NAPI polling for block drivers

Hannes Reinecke
2017-01-11T16:22:39Z

On 01/11/2017 05:12 PM, hch@infradead.org wrote:
> On Wed, Jan 11, 2017 at 04:08:31PM +0000, Bart Van Assche wrote:
>> A typical Ethernet network adapter delays the generation of an interrupt
>> after it has received a packet. A typical block device or HBA does not delay
>> the generation of an interrupt that reports an I/O completion.
>
> NVMe allows for configurable interrupt coalescing, as do a few modern
> SCSI HBAs.

Essentially every modern SCSI HBA does interrupt coalescing; otherwise
the queuing interface won't work efficiently.

Cheers,

Hannes
--
Dr. Hannes Reinecke Teamlead Storage & Networking
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