On Wed, 2017-01-11 at 17:22 +0100, Hannes Reinecke wrote:

On 01/11/2017 05:12 PM, hch@infradead.org wrote:

quoted

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 no=

t

quoted

quoted

delay
the generation of an interrupt that reports an I/O completion.

=20
NVMe allows for configurable interrupt coalescing, as do a few modern
SCSI HBAs.

=20
Essentially every modern SCSI HBA does interrupt coalescing; otherwise
the queuing interface won't work efficiently.

Hello Hannes,

The first e-mail in this e-mail thread referred to measurements against a
block device for which interrupt coalescing was not enabled. I think that
the measurements have to be repeated against a block device for which
interrupt coalescing is enabled.

Bart.=