ZPOOL_TRIM_RATE
fnvlist_add_uint64(args, ZPOOL_TRIM_RATE, rate);
fnvlist_add_uint64(optional, ZPOOL_TRIM_RATE, 1ULL << 30);
{ZPOOL_TRIM_RATE, DATA_TYPE_UINT64, ZK_OPTIONAL},
if (nvlist_lookup_uint64(innvl, ZPOOL_TRIM_RATE, &rate) != 0)