numam-spdk/test/nvme/overhead
Seth Howell c58d3c445b mk: Add all external libs to sys_libs
This allows us to better distinguish between external and internal libs.
This series is aimed at fixing github issue 434
Change-Id: I2ed141f909e7c4a800df02061007b0d23da25380
Signed-off-by: Seth Howell <seth.howell@intel.com>
Reviewed-on: https://review.gerrithub.io/425434
Chandler-Test-Pool: SPDK Automated Test System <sys_sgsw@intel.com>
Tested-by: SPDK CI Jenkins <sys_sgci@intel.com>
Reviewed-by: Ben Walker <benjamin.walker@intel.com>
Reviewed-by: Lance Hartmann <lance.hartmann@oracle.com>
Reviewed-by: Shuhei Matsumoto <shuhei.matsumoto.xt@hitachi.com>
Reviewed-by: Jim Harris <james.r.harris@intel.com>
2018-09-14 22:56:46 +00:00
..
.gitignore test: move lib/nvme up one directory 2018-03-27 00:46:52 -04:00
Makefile mk: Add all external libs to sys_libs 2018-09-14 22:56:46 +00:00
overhead.c nvme/overhead: fix a memory leak issue 2018-08-21 16:52:59 +00:00
README test: move lib/nvme up one directory 2018-03-27 00:46:52 -04:00

This application measures the software overhead of I/O submission
and completion for both the SPDK NVMe driver and an AIO file handle.
It runs a random read, queue depth = 1 workload to a single device,
and captures TSC as follows:

* Submission: capture TSC before and after the I/O submission
  call (SPDK or AIO).
* Completion: capture TSC before and after the I/O completion
  check.  Only record the TSC delta if the I/O completion check
  resulted in a completed I/O.  Also use heuristics in the AIO
  case to account for time spent in interrupt handling outside
  of the actual I/O completion check.

Usage:

To test software overhead for a 4KB I/O over a 10 second period:

SPDK:  overhead -s 4096 -t 10
AIO:   overhead -s 4096 -t 10 /dev/nvme0n1

Note that for the SPDK case, it will only use the first namespace
on the first controller found by SPDK.  If a different namespace is
desired, attach controllers individually to the kernel NVMe driver
to ensure they will not be enumerated by SPDK.