X-Git-Url: https://git.kernel.dk/?a=blobdiff_plain;f=HOWTO;h=57d3fb7f1e4de2484e071d428eab3f66de1038c4;hb=74a92cdd178ac5434d2bbbc1649fe66ff341c1d0;hp=c73b9ecdc859a8912718968918fe837543a258b7;hpb=99b9a85a2962b4792f92d167fc66744a9ebb1128;p=fio.git

diff --git a/HOWTO b/HOWTO
index c73b9ecd..57d3fb7f 100644
--- a/HOWTO
+++ b/HOWTO
@@ -594,9 +594,12 @@ scramble_buffers=bool	If refill_buffers is too costly and the target is
 buffer_compress_percentage=int	If this is set, then fio will attempt to
 		provide IO buffer content (on WRITEs) that compress to
 		the specified level. Fio does this by providing a mix of
-		random data and zeroes. Note that this is per block size
-		unit, for file/disk wide compression level that matches
-		this setting, you'll also want to set refill_buffers.
+		random data and a fixed pattern. The fixed pattern is either
+		zeroes, or the pattern specified by buffer_pattern. If the
+		pattern option is used, it might skew the compression ratio
+		slightly. Note that this is per block size unit, for file/disk
+		wide compression level that matches this setting, you'll also
+		want to set refill_buffers.
 
 buffer_compress_chunk=int	See buffer_compress_percentage. This
 		setting allows fio to manage how big the ranges of random