update documentation for falloc and e4defrag engines
Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
diff --git a/HOWTO b/HOWTO
index 3eb5510..2f70b94 100644
--- a/HOWTO
+++ b/HOWTO
@@ -602,8 +602,16 @@
channel semantics (Send/Recv) for the
InfiniBand, RoCE and iWARP protocols.
- falloc Perform fallocate/punch_hole to files
-
+ falloc IO engine that does regular fallocate to
+ simulate data transfer as fio ioengine.
+ DDIR_READ does fallocate(,mode = keep_size,)
+ DDIR_WRITE does fallocate(,mode = 0)
+ DDIR_TRIM does fallocate(,mode = punch_hole)
+
+ e4defrag IO engine that does regular EXT4_IOC_MOVE_EXT
+ ioctls to simulate defragment activity in
+ request to DDIR_WRITE event
+
external Prefix to specify loading an external
IO engine object file. Append the engine
filename, eg ioengine=external:/tmp/foo.o
@@ -1318,6 +1326,14 @@
[net] listen For TCP network connections, tell fio to listen for incoming
connections rather than initiating an outgoing connection. The
hostname must be omitted if this option is used.
+[e4defrag] donorname=str
+ File will be used as a block donor(swap extents between files)
+[e4defrag] inplace=int
+ Configure donor file blocks allocation strategy
+ 0(default): Preallocate donor's file on init
+ 1 : allocate space immidietly inside defragment event,
+ and free right after event
+
6.0 Interpreting the output