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1 Object-auditor 的启动

Object-auditor的启动和object-replicator的启动过程是一样的，首先是执行启动脚本

swift-init object-auditor start

if __name__ == '__main__':
    parser = OptionParser("%prog CONFIG [options]")
    parser.add_option('-z', '--zero_byte_fps',
                      help='Audit only zero byte files at specified files/sec')
    parser.add_option('-d', '--devices',
                      help='Audit only given devices. Comma-separated list')
    conf_file, options = parse_options(parser=parser, once=True)
    run_daemon(ObjectAuditor, conf_file, **options)

def run_forever(self, *args, **kwargs):
        """Run the object audit until stopped."""
        # zero byte only command line option
        zbo_fps = kwargs.get('zero_byte_fps', 0)
        parent = False
        if zbo_fps:
            # only start parent
            parent = True
        kwargs = {'mode': 'forever'}

        while True:
            try:
                #循环审计
                self.audit_loop(parent, zbo_fps, **kwargs)
            except (Exception, Timeout) as err:
                self.logger.exception(_('ERROR auditing: %s' % err))
            #每隔30秒执行一次
            self._sleep()

   def audit_loop(self, parent, zbo_fps, override_devices=None, **kwargs):
        """Audit loop"""
        self.clear_recon_cache('ALL')
        self.clear_recon_cache('ZBF')
        kwargs['device_dirs'] = override_devices    #获得需要重写的设备
        #第一次启动 parent 为false
        if parent:
            kwargs['zero_byte_fps'] = zbo_fps
            #运行 run_audit方法
            self.run_audit(**kwargs)
        else:
            pids = []
            # self.conf_zero_byte_fps = int(conf.get('zero_byte_files_per_second', 50))
            if self.conf_zero_byte_fps:
                zbf_pid = self.fork_child(zero_byte_fps=True, **kwargs)
                #将子进程加入到pids中
                pids.append(zbf_pid)
            pids.append(self.fork_child(**kwargs))
            #
            while pids:
                pid = os.wait()[0]
                # ZBF scanner must be restarted as soon as it finishes
                if self.conf_zero_byte_fps and pid == zbf_pid and                    len(pids) > 1:
                    kwargs['device_dirs'] = override_devices
                    zbf_pid = self.fork_child(zero_byte_fps=True, **kwargs)
                    pids.append(zbf_pid)
                pids.remove(pid)

    def fork_child(self, zero_byte_fps=False, **kwargs):
        """Child execution"""
        #返回子进程的进程号
        pid = os.fork()
        if pid:
            return pid
        else:
            signal.signal(signal.SIGTERM, signal.SIG_DFL)
            if zero_byte_fps:
                kwargs['zero_byte_fps'] = self.conf_zero_byte_fps
            #运行审计
            self.run_audit(**kwargs)
            sys.exit()

def run_audit(self, **kwargs):
        """Run the object audit"""
        mode = kwargs.get('mode')
        zero_byte_only_at_fps = kwargs.get('zero_byte_fps', 0)
        device_dirs = kwargs.get('device_dirs')

        worker = AuditorWorker(self.conf, self.logger, self.rcache,
                               self.devices,
                               zero_byte_only_at_fps=zero_byte_only_at_fps)
        #审计所有的对象
        worker.audit_all_objects(mode=mode, device_dirs=device_dirs)

下一篇博客中重点介绍具体执行审计的AuditorWorker类的实现以及对于损坏的文件是如何创建隔离区的。

由于本人水平有限，文中难免出现理解错误，敬请指正、交流，谢谢！

OpenStack_Swift源码分析——Object-auditor源码分析(1),布布扣,bubuko.com

OpenStack_Swift源码分析——Object-auditor源码分析(1)

标签：openstack   源码   swift   存储   对象   

原文地址：http://blog.csdn.net/xianghonglee/article/details/25922797