-The section switch is meant to make it easier to ship a bigger job file
-instead of several smaller ones. Say you define a job file with light,
-moderate, and heavy parts. Then you can ask fio to run the given part
-only by giving it a --section=heavy command line option. The section
-option only applies to job sections, the reserved 'global' section is
-always parsed and taken into account.
+The --section option allows one to combine related jobs into one file.
+E.g. one job file could define light, moderate, and heavy sections. Tell fio to
+run only the "heavy" section by giving --section=heavy command line option.
+One can also specify the "write" operations in one section and "verify"
+operation in another section. The --section option only applies to job
+sections. The reserved 'global' section is always parsed and used.
+
+The --alloc-size switch allows one to use a larger pool size for smalloc.
+If running large jobs with randommap enabled, fio can run out of memory.
+Smalloc is an internal allocator for shared structures from a fixed size
+memory pool. The pool size defaults to 1024k and can grow to 128 pools.