Incorrect VM IOPS metrics

### problem

VM metrics show incorrect IOPS. This may be related to the type of my primary storage. I’m using Linstor. When we perform a fio test, we get the following results:

But VM metrics shows in this time:

### versions

ACS 4.19.3
Primary storage - Linstor 1.31.3
OS: Ubuntu 24.04.2

### The steps to reproduce the bug

Just perform a fio test and check the metrics.

### What to do about it?

It would be great if this metric could be fixed.

在 Ubuntu 24.04.2 上针对 Apache CloudStack 4.19.3 和 Linstor 1.31.3 重现 fio 测试，然后将 fio 结果与同一时间段内的 VM IOPS 指标进行比较。从 VM 指标入口点跟踪指标计算；当报告的 IOPS 与观测到的存储结果匹配时，即表示完成。

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