使用MySQL进行juicefs bench 测试，write small file和官网测试有4倍的差距

[davidzhangbj]

测试集群配置：阿里云 ecs.c6.2xlarge 8C16G
JuiceFS版本：1.22

MySQL版本：8.0.32，使用Docker部署在同一个服务器上

测试命令及结果：

write small file 只有21.6 files/s，官网有82.30 files/s
有什么建议吗，怎样调整才能达到官网的水平？

[frostwind]

感觉你的mysql meta engine的速度不是很理想，update meta都11ms了。试试看mysql用innodb_flush_log_at_trx_commit=0 或者2 看看有没有改善？
下面是我的用on-prem ceph + postgresql as meta engine的测试

# juicefs bench -p 4 /shared/jfs/myjfs/
  Write big blocks: 4096/4096 [==============================================================]  1375.3/s used: 2.978199224s
   Read big blocks: 4096/4096 [==============================================================]  882.6/s  used: 4.640805437s
Write small blocks: 400/400 [==============================================================]  246.3/s  used: 1.624222509s
 Read small blocks: 400/400 [==============================================================]  1482.2/s used: 270.002264ms
  Stat small files: 400/400 [==============================================================]  5257.4/s used: 76.148367ms 
Benchmark finished!
BlockSize: 1.0 MiB, BigFileSize: 1.0 GiB, SmallFileSize: 128 KiB, SmallFileCount: 100, NumThreads: 4
Time used: 14.8 s, CPU: 176.1%, Memory: 549.6 MiB
+------------------+------------------+---------------+
|       ITEM       |       VALUE      |      COST     |
+------------------+------------------+---------------+
|   Write big file |    1376.60 MiB/s |   2.98 s/file |
|    Read big file |     882.75 MiB/s |   4.64 s/file |
| Write small file |    246.4 files/s | 16.23 ms/file |
|  Read small file |   1487.5 files/s |  2.69 ms/file |
|        Stat file |   5305.9 files/s |  0.75 ms/file |
|   FUSE operation | 75908 operations |    0.36 ms/op |
|      Update meta |  6603 operations |    1.10 ms/op |
|       Put object |  1424 operations |   25.09 ms/op |
|       Get object |  1024 operations |   63.51 ms/op |
|    Delete object |  1424 operations |    2.64 ms/op |
| Write into cache |   400 operations |    1.04 ms/op |
|  Read from cache |   400 operations |    0.23 ms/op |
+------------------+------------------+---------------+