Document that write_iolog is unsafe for concurrent jobs

[fio.git] / HOWTO

diff --git a/HOWTO b/HOWTO
index dc21afc039d36456e41ea215b4c2917274ecc74f..7c943294ecfb838ec79ab1f6d558ab4390e2be32 100644 (file)
--- a/HOWTO
+++ b/HOWTO
@@ -988,7 +988,8 @@ zoneskip=int        Skip the specified number of bytes when zonesize data has
                io on zones of a file.
 
 write_iolog=str        Write the issued io patterns to the specified file. See
-               read_iolog.
+               read_iolog.  Specify a separate file for each job, otherwise
+               the iologs will be interspersed and the file may be corrupt.
 
 read_iolog=str Open an iolog with the specified file name and replay the
                io patterns it contains. This can be used to store a