Spdk/overhead at 06b537bfdb4393dea857e204b85d8df46a351d8a - Spdk

History

John Kariuki 057c92e3d8 test/app_overhead: fix aio make issue AIO not working because the check for $OS==Linux is before the $OS is set. Therefore, the binary build does not include libaio Change-Id: Iab862d0113d637134a5275d46252c60fe27dde5e Signed-off-by: John Kariuki <John.K.Kariuki@intel.com> Reviewed-on: https://review.spdk.io/gerrit/c/spdk/spdk/+/4516 Reviewed-by: Mellanox Build Bot Reviewed-by: Shuhei Matsumoto <shuhei.matsumoto.xt@hitachi.com> Reviewed-by: Tomasz Zawadzki <tomasz.zawadzki@intel.com> Community-CI: Broadcom CI Tested-by: SPDK CI Jenkins <sys_sgci@intel.com>		2020-10-07 07:47:41 +00:00
..
.gitignore	test: move lib/nvme up one directory	2018-03-27 00:46:52 -04:00
Makefile	test/app_overhead: fix aio make issue	2020-10-07 07:47:41 +00:00
overhead.c	test/nvme_overhead&startup: Replace next pointer by TAILQ	2020-10-05 08:27:56 +00:00
README	test: move lib/nvme up one directory	2018-03-27 00:46:52 -04:00

README

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.