dmu_object_set_compress
dmu_object_set_compress(os, bigobj, comp, tx);
dmu_object_set_compress(rwa->os, drro->drr_object,
dmu_object_set_compress(spa->spa_meta_objset, obj,
void dmu_object_set_compress(objset_t *os, uint64_t object, uint8_t compress,