Summary

Change the accepted minimum value of InitialSurvivorRatio.

Problem

The minimum accepted value of MinSurvivorRatio is 3, which sets the lower bound for accepted InitialSurvivorRatio, because of the invariant that InitialSurvivorRatio >= MinSurvivorRatio. However, the current minimum accepted value is 0, and will be adjusted silently to 3 at startup.

Solution

Change the accepted ranged of InitialSurvivorRatio so that invalid values are reported, not silently ignored. In this case, users should either drop InitialSurvivorRatio on cmdline or pick a value in the valid range [3, max_uintx].

Specification

  product(uintx, MinSurvivorRatio, 3,                                        \
          "Minimum ratio of young generation/survivor space size")           \
          range(3, max_uintx)                                                \

   product(uintx, InitialSurvivorRatio, 8,                                   \
           "Initial ratio of young generation/survivor space size")          \
-          range(0, max_uintx)                                               \
+          range(3, max_uintx)                                               \