private boolean isSplitNeeded(final RegionHeartbeatRequest request, final Pair<Region, RegionStats> modelWorker) {
        if (modelWorker == null) {
            return false;
        }
        final long modelApproximateKeys = modelWorker.getValue().getApproximateKeys();
        if (request.getLeastKeysOnSplit() > modelApproximateKeys) {
            return false;
        }
        final Region modelRegion = modelWorker.getKey();
        final List<Pair<Region, RegionStats>> regionStatsList = request.getRegionStatsList();
        for (final Pair<Region, RegionStats> p : regionStatsList) {
            if (modelRegion.equals(p.getKey())) {
                return true;
            }
        }
        return false;
    }
Range split judge, the reference indicator for splitting is the
region's approximate keys.

@author jiachun.fjc
jraft-rheakv/rheakv-pd/src/main/java/com/alipay/sofa/jraft/rhea/pipeline/handler/SplittingJudgeByApproximateKeysHandler.java