Establish scrub status on first execution and keep it.

@return bool
772140
public function isScrubbed()
    {
        if (null === $this->scrubbed) {
            $this->resetRandomGeneratorByContact();
            $this->scrubbed = $this->scrubRate > rand(0, 99);
        }

        return $this->scrubbed;
    }
1026182
public function actionClearAll()
    {
        $caches = $this->findCaches();
        $cachesInfo = [];

        if (empty($caches)) {
            $this->notifyNoCachesFound();
            return ExitCode::OK;
        }

        foreach ($caches as $name => $class) {
            $cachesInfo[] = [
                'name' => $name,
                'class' => $class,
                'is_flushed' => $this->canBeCleared($class) ? $this->app->get($name)->clear() : false,
            ];
        }

        $this->notifyCleared($cachesInfo);
    }
413127
public function purge() {
        if ($this->isready) {
            $this->collection->drop();
            $this->collection = $this->database->selectCollection($this->definitionhash);
        }

        return true;
    }
507891
public function flush()
    {
        if (! $this->files->isDirectory($this->directory)) {
            return false;
        }

        foreach ($this->files->directories($this->directory) as $directory) {
            if (! $this->files->deleteDirectory($directory)) {
                return false;
            }
        }

        return true;
    }
487547
public function purge() {
        $this->flush_store_by_id($this->storeid);
        $this->store = &self::register_store_id($this->storeid);
        // Don't worry about checking if we're using max size just set it as thats as fast as the check.
        $this->storecount = 0;
        return true;
    }
248035
public function isClean()
    {
        if ($this->getConfigFileAge() > max($this->getSassMaxAge(), $this->getStylesheetsMaxAge())) {
            return false;
        }

        return $this->getSassMaxAge() <= $this->getStylesheetsMaxAge();
    }
324528
public function flush()
    {
        $i = 0;
        $count = $this->count();

        while ($i < $count) {
            if (xcache_clear_cache(XC_TYPE_VAR, $i) === false) {
                return false;
            }

            $i++;
        }

        return true;
    }
325980
public function flush()
    {
        // this may take a while, but they shouldn't be flushing in production
        $cache_keys = $this->redis->keys(/* prefixed with cache: */ '*');

        foreach ($cache_keys as $key) {
            $this->redis->del($key);
        }

        unset($cache_keys);

        return true;
    }
250030
public function flushBatch() {
		if(count($this->batch) > 0) {
			$this->insertMany($this->batch, $this->batch_replace);
			$this->batch = [];
			return true;
		}
		return false;
	}
601854
public function isOutdated()
    {
        $this->boot();

        $compiled_tracked_files = new TrackedFiles([$this->output_dir]);
        $current_tracked_files  = new TrackedFiles($this->paths);

        if ($current_tracked_files->modifiedAfter($compiled_tracked_files)) {
            $this->profiler->set('tracker.reason', 'One of the tracked files has been modified.');
            return true;
        }

        $this->profiler->set('tracker.reason', false);
        return false;
    }
1002775
public function flush()
    {
        if (!$this->config["blocking"] && !empty($this->asyncBuffer)) {
            $wrote = fwrite($this->destinationHandler, $this->asyncBuffer);
            $this->asyncBuffer = substr($this->asyncBuffer, $wrote);
        }

        return empty($this->asyncBuffer);
    }
544093
public function flush()
    {
        if (empty($this->memcache)) {
            return false;
        }

        $flushStatus = $this->memcache->flush();

        return $flushStatus;
    }
1181457
public function flush() {
		$event  = $this->getProfiler()->startDelete('Flush');
		$result = $this->getBackend()->flush();
		
		if ($result === false) {
			$event->stopError();
		} else {
			$event->stopSuccess();
		}
		
		return $result;
	}
1012908
public function flush() {
    $request = new MemcacheFlushRequest();
    $response = new MemcacheFlushResponse();

    try {
      ApiProxy::makeSyncCall('memcache', 'FlushAll', $request, $response);
    } catch (Error $e) {
      return false;
    }
    return true;
  }
235591
public function flush()
    {
        $this->aliases = [];
        $this->resolved = [];
        $this->bindings = [];
        $this->instances = [];
        $this->abstractAliases = [];
    }
1016396
public function flush()
    {
        $flushCallback = function ($allFlushed, $cache) {
            return $allFlushed && $cache->flush();
        };
        return array_reduce($this->caches, $flushCallback, true);
    }
87081
public function flush(){
        $url = $this->apiUrl.'/cgi-bin/menu/delete?access_token='.$this->getAccessToken();
        $result = $this->curl($url);
        return $this->get($result);
    }