From: Tomohiro Kusumi <tkusumi@xxxxxxxxxx> Add "in bytes" and "A percentage can be specified by ...", based on an email post titled "in what units is offset option?". -- example of offset in percentage # ./fio --debug=parse --name=xxxxx --ioengine=sync --rw=rw --size=1m --unlink=1 --offset=-51 | grep "SET start_offset_percent" parse 12859 SET start_offset_percent 50 Signed-off-by: Tomohiro Kusumi <tkusumi@xxxxxxxxxx> --- HOWTO | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/HOWTO b/HOWTO index 2007dc0..8e11052 100644 --- a/HOWTO +++ b/HOWTO @@ -1090,11 +1090,13 @@ I/O type .. option:: offset=int - Start I/O at the provided offset in the file, given as either a fixed size or - a percentage. If a percentage is given, the next ``blockalign``-ed offset - will be used. Data before the given offset will not be touched. This + Start I/O at the provided offset in the file, given as either a fixed size in + bytes or a percentage. If a percentage is given, the next ``blockalign``-ed + offset will be used. Data before the given offset will not be touched. This effectively caps the file size at `real_size - offset`. Can be combined with :option:`size` to constrain the start and end range of the I/O workload. + A percentage can be specified by the percentage number plus 1 with preceding '-'. + For example, -1 is parsed as 0%, -10 is parsed as 9%, -101 is parsed as 100%. .. option:: offset_increment=int -- 2.9.4 -- To unsubscribe from this list: send the line "unsubscribe fio" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
