class CleanSpaceService extends ShutdownAbleThread {
        ...
        @Override
        public void doWork() {
            try {
                storeBaseRatio = DLedgerUtils.getDiskPartitionSpaceUsedPercent(dLedgerConfig.getStoreBaseDir());
                dataRatio = calcDataStorePathPhysicRatio();
                long hourOfMs = 3600L * 1000L;
                long fileReservedTimeMs = dLedgerConfig.getFileReservedHours() * hourOfMs;
                if (fileReservedTimeMs < hourOfMs) {
                    logger.warn("The fileReservedTimeMs={} is smaller than hourOfMs={}", fileReservedTimeMs, hourOfMs);
                    fileReservedTimeMs = hourOfMs;
                }
                //If the disk is full, should prevent more data to get in
                DLedgerMmapFileStore.this.isDiskFull = isNeedForbiddenWrite();
                boolean timeUp = isTimeToDelete();
                boolean checkExpired = isNeedCheckExpired();
                boolean forceClean = isNeedForceClean();
                boolean enableForceClean = dLedgerConfig.isEnableDiskForceClean();
                int intervalForcibly = 120 * 1000;
                if (timeUp || checkExpired) {
                    int count = getDataFileList().deleteExpiredFileByTime(fileReservedTimeMs, 100, intervalForcibly, forceClean && enableForceClean);
                    if (count > 0 || (forceClean && enableForceClean) || isDiskFull) {
                        logger.info("Clean space count={} timeUp={} checkExpired={} forceClean={} enableForceClean={} diskFull={} storeBaseRatio={} dataRatio={}",
                            count, timeUp, checkExpired, forceClean, enableForceClean, isDiskFull, storeBaseRatio, dataRatio);
                    }
                    if (count > 0) {
                        DLedgerMmapFileStore.this.reviseLedgerBeforeBeginIndex();
                    }
                }
                getDataFileList().retryDeleteFirstFile(intervalForcibly);
                waitForRunning(100);
            } catch (Throwable t) {
                logger.info("Error in {}", getName(), t);
                DLedgerUtils.sleep(200);
            }
        }
        ...
}