Modify the memsubsys1-3.1.4 test so that it does not fail arbitrarily due

to variations in the behavior of system malloc().

FossilOrigin-Name: d280157da0b5275f3e3c875d2dcfb9998d374ac0

test/memsubsys1.test

@@ -124,7 +124,13 @@ do_test memsubsys1-3.1.3 {
 } 0
 do_test memsubsys1-3.1.4 {
   set overflow [lindex [sqlite3_status SQLITE_STATUS_PAGECACHE_OVERFLOW 0] 2]
-} $max_pagecache
+  # Note:  The measured PAGECACHE_OVERFLOW is amount malloc() returns, not what
+  # was requested.  System malloc() implementations might (arbitrarily) return
+  # slightly different oversize buffers, which can result in slightly different
+  # PAGECACHE_OVERFLOW sizes between consecutive runs.  So we cannot do an
+  # exact comparison.  Simply verify that the amount is within 5%.
+  expr {$overflow>=$max_pagecache*0.95 && $overflow<=$max_pagecache*1.05}
+} 1
 do_test memsubsys1-3.1.5 {
   set s_used [lindex [sqlite3_status SQLITE_STATUS_SCRATCH_USED 0] 2]
 } 0