Commit 3dc37c43 authored by Ziye Yang's avatar Ziye Yang Committed by Daniel Verkamp
Browse files

doc/nvmf: Update NVMe-oF target user guide. 



Reason: Core binding is not supported in NVMe-OF
subsystem anymore.

Change-Id: I92a876bf1a150b7833ebb049f3284e589f187edc
Signed-off-by: default avatarZiye Yang <optimistyzy@gmail.com>
Reviewed-on: https://review.gerrithub.io/392914


Tested-by: default avatarSPDK Automated Test System <sys_sgsw@intel.com>
Reviewed-by: default avatarDaniel Verkamp <daniel.verkamp@intel.com>
Reviewed-by: default avatarBen Walker <benjamin.walker@intel.com>
parent fe8138ce

doc/nvmf.md

+7 −13
Original line number Diff line number Diff line
@@ -137,9 +137,9 @@ nvme disconnect -n "nqn.2016-06.io.spdk:cnode1" 
SPDK uses the [DPDK Environment Abstraction Layer](http://dpdk.org/doc/guides/prog_guide/env_abstraction_layer.html)

to gain access to hardware resources such as huge memory pages and CPU core(s). DPDK EAL provides

functions to assign threads to specific cores.

To ensure the SPDK NVMe-oF target has the best performance, configure the RNICs, NVMe

devices, and the core assigned to the NVMe-oF subsystem to all be located on the same NUMA node.

The following parameters are used to control which CPU cores SPDK executes on:

To ensure the SPDK NVMe-oF target has the best performance, configure the RNICs and NVMe devices to

be located on the same NUMA node. The following parameters in the configuration file

are used to configure SPDK NVMe-oF target:



**ReactorMask:** A hexadecimal bit mask of the CPU cores that SPDK is allowed to execute work

items on. The ReactorMask is located in the [Global] section of the configuration file. For example,
@@ -148,9 +148,8 @@ to assign lcores 24,25,26 and 27 to NVMe-oF work items, set the ReactorMask to: 
ReactorMask 0xF000000

~~~



**Assign each Subsystem to a CPU core:** This is accomplished by specifying the "Core" value in

the [Subsystem] section of the configuration file. For example,

to assign the Subsystems to lcores 25 and 26:

**Subsystem configuration:** the [Subsystem] section in the configuration file is used to configure

subysystems for the NVMe-oF target.

~~~{.sh}

[Nvme]

TransportID "trtype:PCIe traddr:0000:02:00.0" Nvme0
@@ -158,7 +157,6 @@ TransportID "trtype:PCIe traddr:0000:82:00.0" Nvme1 


[Subsystem1]

NQN nqn.2016-06.io.spdk:cnode1

Core 25

Listen RDMA 192.168.100.8:4420

AllowAnyHost No

Host nqn.2016-06.io.spdk:init
@@ -167,16 +165,13 @@ Namespace Nvme0n1 1 


[Subsystem2]

NQN nqn.2016-06.io.spdk:cnode2

Core 26

Listen RDMA 192.168.100.9:4420

AllowAnyHost Yes

SN SPDK00000000000002

Namespace Nvme1n1 1

~~~

SPDK executes all code for an NVMe-oF subsystem on a single thread. Different subsystems may execute

on different threads. SPDK gives the user maximum control to determine how many CPU cores are used

to execute subsystems. Configuring different subsystems to execute on different CPU cores prevents

the subsystem data from being evicted from limited CPU cache space.

SPDK spreads the execution of requests for a single subsystem across all available cores

in a round-robin manner.



## Emulating an NVMe controller {#nvmf_config_virtual_controller}
@@ -194,7 +189,6 @@ available as NSID 1 and 2: 
# Virtual controller

[Subsystem2]

  NQN nqn.2016-06.io.spdk:cnode2

  Core 0

  Listen RDMA 192.168.2.21:4420

  AllowAnyHost No

  Host nqn.2016-06.io.spdk:init