Customer is using database on Oceanstor 5500T V2 storage, and found the database is slow, response time is too high.
no alarm in storage and database.
1, According to the phenomenon, the response time on database is high, we need check the storage performance data on the LUN for the database.
2,Collect the storage log and performance log. (log collection method please refer to the product documentation)
3, Check the read IO response time as below, from below performance data, we can see sometimes the read IO response time is larger than 50ms which is higher than usual.
4, and check write response time, it is less than 10ms, which is normal.
5, According to above information, the performance issue is related to the read performance , and because the IO write is to the cache, the performance bottleneck could be from the disk .
6, Then check the disk usage, and from the performance data, we can see that all the SATA disk usage are very high ,and SAS disk usage is low.
7, After above analyze , it is clear that the pressure on SATA disk is high, and there is not so much pressure on SAS disk. In this situation, we need enable the smarttier function.
Smarttier function is not enabled and the SATA disk take too much pressure.
Enable the smarttier function.
this issue could happen on all of the storage version.