public long estimatedSize() {
        if (this.estimatedSize > 0) {
            return this.estimatedSize;
        }

        this.estimatedSize = 140L + estimatedSize(this.learners) + //
                             estimatedSize(this.oldLearners) + //
                             estimatedSize(this.peers) + //
                             estimatedSize(this.oldPeers) + //
                             (this.data != null ? this.data.remaining() : 0) + 56;

        return this.estimatedSize;
    }
true when the log has checksum *
jraft-core/src/main/java/com/alipay/sofa/jraft/entity/LogEntry.java