On 01/11/2017 09:12 AM, hch@infradead.org wrote:

On Wed, Jan 11, 2017 at 04:08:31PM +0000, Bart Van Assche wrote:

quoted

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.

Unfortunately it's way too coarse on NVMe, with the timer being in 100
usec increments... I've had mixed success with the depth trigger.

-- 
Jens Axboe