Add a note of what is the default value for random_generator

Signed-off-by: Jens Axboe <axboe@fb.com>

diff --git a/HOWTO b/HOWTO
index 7c24c1b74296aa33cdff97eca9458defd291b6ca..4a910a1ac11716d57c3885cf2c2f4fd63f0fa944 100644 (file)
--- a/HOWTO
+++ b/HOWTO
@@ -1013,7 +1013,9 @@ random_generator=str      Fio supports the following engines for generating
                typically good enough. LFSR only works with single
                block sizes, not with workloads that use multiple block
                sizes. If used with such a workload, fio may read or write
-               some blocks multiple times.
+               some blocks multiple times. The default value is tausworthe,
+               unless the required space exceeds 2^32 blocks. If it does,
+               then tausworthe64 is selected automatically.
 
 nice=int       Run the job with the given nice value. See man nice(2).
 

diff --git a/fio.1 b/fio.1
index 7bdfea3f019f54780b57e5baec828e5708770239..6cc6379e14bc7718362d00fe226f9a4f2cb51cb4 100644 (file)
--- a/fio.1
+++ b/fio.1
@@ -920,7 +920,9 @@ guarantees that we never generate the same offset twice, and it's also less
 computationally expensive. It's not a true random generator, however, though
 for IO purposes it's typically good enough. LFSR only works with single block
 sizes, not with workloads that use multiple block sizes. If used with such a
-workload, fio may read or write some blocks multiple times.
+workload, fio may read or write some blocks multiple times. The default
+value is tausworthe, unless the required space exceeds 2^32 blocks. If it does,
+then tausworthe64 is selected automatically.
 .TP
 .BI nice \fR=\fPint
 Run job with given nice value.  See \fBnice\fR\|(2).