Fix posix_memalign() return value in case of error

[fio.git] / fio.1

diff --git a/fio.1 b/fio.1
index 10b1768ce42e9eb712f77202549c0b76795695ad..4445d0a3a99989191c70e8359e8c8bc82248613e 100644 (file)
--- a/fio.1
+++ b/fio.1
@@ -515,7 +515,11 @@ Same as \fBmmap\fR, but use huge files as backing.
 The amount of memory allocated is the maximum allowed \fBblocksize\fR for the
 job multiplied by \fBiodepth\fR.  For \fBshmhuge\fR or \fBmmaphuge\fR to work,
 the system must have free huge pages allocated.  \fBmmaphuge\fR also needs to
-have hugetlbfs mounted, and \fIfile\fR must point there.
+have hugetlbfs mounted, and \fIfile\fR must point there. At least on Linux,
+huge pages must be manually allocated. See \fB/proc/sys/vm/nr_hugehages\fR
+and the documentation for that. Normally you just need to echo an appropriate
+number, eg echoing 8 will ensure that the OS has 8 huge pages ready for
+use.
 .RE
 .TP
 .BI iomem_align \fR=\fPint
@@ -579,9 +583,10 @@ Write extra information about each I/O (timestamp, block number, etc.). The
 block number is verified.
 .TP
 .B pattern
-Fill I/O buffers with a specific pattern that is used to verify.  The pattern is
-specified by appending `:\fIint\fR' to the parameter. \fIint\fR cannot be larger
-than 32-bits. 
+Fill I/O buffers with a specific pattern that is used to verify. If the pattern
+is < 4bytes, it can either be a decimal or a hexadecimal number. If the pattern
+is > 4bytes, currently, it can only be a hexadecimal pattern starting with
+either "0x" or "0X".
 .TP
 .B null
 Pretend to verify.  Used for testing internals.