Write time latency is higher than read time latency

Copper Contributor

Few days ago we connected our Exchange servers to our monitoring system (Zabbix).

 

Short after this we received lots alerts about write time latency is higher than read time latency for all database instances.
Monitoring system checks "MSExchange Database ==> Instances(*)\I/O Database Writes (Recovery) Average Latency" and similar counter for read latency.
On Microsoft web page (https://learn.microsoft.com/en-us/exchange/exchange-2013-performance-counters-exchange-2013-help) I found very short information that write latency should be lee than read latency for same db instance. There is no explanation what could be a reason and how to fix this.

Could anyone please shed some light on the matter, and tell me what is the reason and how to solve it.

 

Thanks in advance

 

2 Replies

@mariuszg-pro 

We have the same issue.

Linked in to monitor the thread.

This is just Zabbix being Zabbix. I assume you are using default template for Microsoft Exchange by Zabbix.

I've seen this recently on one of my brand-new Exchange deployments.
Trigger works like this: If Average (Database Writes Latency) > Average (Database Reads Latency), then throw warning.

The thing is when database is inactive or empty, read latency and write latency are close to 0. But I still have DAG replication, that's why there is some activity on disk. Sometimes I got 0.000015ms for read latency and 0.00002ms for write latency.

Technically Zabbix is right. Write latency is greater then read latency, but it doesn't make sense in my case. The numbers are insignificant.