Clarify reaching capacity before 60 minutes

README

@@ -41,7 +41,8 @@ where
 
 <threads per node> and <blocksize> will be chosen optimally for best
 performance.  <bytes per thread> will be chosen so that the write and
-read phases run for at least 60 minutes each.
+read phases run for at least 60 minutes each or until 95% of the
+filesystem capacity is reached by the write phase.
 
 Results will be evaluated by looking at the "WRITE" and "READ" sections
 in the table output from elbencho on stdout.  The row "Elapsed time" in
@@ -77,7 +78,8 @@ where
 
 <threads per node> will be chosen optimally for best performance.
 <bytes per thread> will be chosen so that the write and read phases runs
-for at least 60 minutes each.
+for at least 60 minutes each or until 95% of the filesystem capacity is
+reached by the write phase.
 
 Results will be evaluated by looking at the "WRITE" and "READ" sections
 in the table output from elbencho on stdout.  The row "Elapsed time" in
@@ -112,7 +114,8 @@ where
 
 <threads per node> will be chosen optimally for best performance.
 <number of files> will be chosen so that each phase; create, stat, and
-delete; runs for at least 60 minutes.
+delete; runs for at least 60 minutes or until 95% of the filesystem's
+maximum number of files is reached by the create phase.
 
 Results will be evaluated by looking at the "WRITE", "STAT", and
 "RMFILES" sections in the table output from elbencho on stdout.  The