Checkpoint loguniq 请教！

nicolasch

两台服务器，分别做dbimport导入同一个数据文件，结果机器配置差的花了一个小时，机器配置好的花了二个小时，看日志，
慢的
00:01:21  Checkpoint Completed:  duration was 0 seconds.
00:01:21  Checkpoint loguniq 275, logpos 0xc240a8
00:06:25  Checkpoint Completed:  duration was 0 seconds.
00:06:25  Checkpoint loguniq 275, logpos 0xc96018
快的
12:52:50  Checkpoint Completed:  duration was 0 seconds.
12:52:50  Checkpoint loguniq 1792, logpos 0x153a9098
12:57:56  Checkpoint Completed:  duration was 0 seconds.
12:57:56  Checkpoint loguniq 1792, logpos 0x153f31f0
想请教一下Checkpoint loguniq 后面的数字为何相差这么大，他表示什么意思，是不是这个原因造成机器配置好的服务器反而慢。谢谢！

liaosnet

loguniq 是指逻辑日志的唯一序号~~用得久的数据库这个id会比较大~

从你这只能看到两个机子的checkpoint的间隔都是5分钟,还有就是 "慢的"那台服务器的数据库是更近安装的而已..

yunzhongyue

liaosnet好敬业好有速度啊！

nicolasch

昨晚又试了一次，发现 duration 的延迟很长，请各位看看
17:00:37  Checkpoint Completed:  duration was 150 seconds.
17:00:37  Checkpoint loguniq 1, logpos 0xd78018

17:10:55  Checkpoint Completed:  duration was 313 seconds.
17:10:55  Checkpoint loguniq 1, logpos 0xdea018

17:22:54  Checkpoint Completed:  duration was 414 seconds.
17:22:54  Checkpoint loguniq 1, logpos 0xe4d510

17:28:37  Checkpoint Completed:  duration was 38 seconds.
17:28:37  Checkpoint loguniq 1, logpos 0xe52018

17:34:49  Checkpoint Completed:  duration was 68 seconds.
17:34:49  Checkpoint loguniq 1, logpos 0xe71018

17:51:51  Checkpoint Completed:  duration was 717 seconds.
17:51:51  Checkpoint loguniq 1, logpos 0xf2c018

17:57:52  Checkpoint Completed:  duration was 56 seconds.
17:57:52  Checkpoint loguniq 1, logpos 0xf5c018

liaosnet

回复 4# nicolasch


   持续时间长: 如果你是在import的话,由于在逻辑日志里的记录较多,写回磁盘可以要慢些~

   要不你在环境变量里加上 TRACECKPT=1 ,然后重启跟踪下检查点的时间在做什么..

nicolasch

但是另外一台机器：
12:52:50  Checkpoint Completed:  duration was 0 seconds.
12:52:50  Checkpoint loguniq 1792, logpos 0x153a9098
12:57:56  Checkpoint Completed:  duration was 0 seconds.
12:57:56  Checkpoint loguniq 1792, logpos 0x153f31f0

为什么他的Checkpoint 时间都是0，是不是慢的那台参数设置有问题呢？

liaosnet

回复 6# nicolasch


    所以让你跟踪看下呀~~看它的等待时间是在那?是flush lru还是flush disk