Commit 7fc4405c authored by Daniel Verkamp's avatar Daniel Verkamp Committed by Jim Harris
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doc/bdev: document bdev_null 



Change-Id: I5b48e798b0540ef7fbc99699ebf6dc913c075b44
Signed-off-by: default avatarDaniel Verkamp <daniel.verkamp@intel.com>
Reviewed-on: https://review.gerrithub.io/376861


Tested-by: default avatarSPDK Automated Test System <sys_sgsw@intel.com>
Reviewed-by: default avatarPaul Luse <paul.e.luse@intel.com>
Reviewed-by: default avatarJim Harris <james.r.harris@intel.com>
parent 744a785b

doc/bdev.md

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Original line number Diff line number Diff line
@@ -57,6 +57,21 @@ Configuration file syntax: 
This exports 4 malloc block devices, named Malloc0 through Malloc3.  Each malloc block device will

be 64MB in size.



## Null {#bdev_config_null}



The SPDK null bdev driver is a dummy block I/O target that discards all writes and returns undefined

data for reads.  It is useful for benchmarking the rest of the bdev I/O stack with minimal block

device overhead and for testing configurations that can't easily be created with the Malloc bdev.



Configuration file syntax:

~~~

[Null]

  # Dev <name> <size_in_MiB> <block_size>



  # Create an 8 petabyte null bdev with 4K block size called Null0

  Dev Null0 8589934592 4096

 ~~~



## Linux AIO {#bdev_config_aio}



The SPDK aio bdev driver provides SPDK block layer access to Linux kernel block devices via Linux AIO.