Document loading external io engines
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
diff --git a/HOWTO b/HOWTO
index de4b0a9..745e9c7 100644
--- a/HOWTO
+++ b/HOWTO
@@ -289,6 +289,11 @@
or receive, if the latter only the port
argument is used.
+ external Prefix to specify loading an external
+ IO engine object file. Append the engine
+ filename, eg ioengine=external:/tmp/foo.o
+ to load ioengine foo.o in /tmp.
+
iodepth=int This defines how many io units to keep in flight against
the file. The default is 1 for each file defined in this
job, can be overridden with a larger value for higher