ALM-50840 Number of Mempool Service Failures Exceeds the Threshold Because Concurrent Service Requests Exceed the Upper Limit

Alarm Description

The system checks the number of Mempool service failures due to concurrent service requests exceeding the upper limit every 30 seconds. This alarm is generated when the number of Mempool service failures exceeds the threshold.

This alarm is cleared when the number of Mempool service failures falls below the threshold.

Alarm Attributes

Alarm Parameters

Impact on the System

The server efficiency decreases, and tasks may fail.

Possible Causes

• The load tilt is too large, and the load pressure is too high.
• The upper limit for concurrent Mempool service requests is too small.

Handling Procedure

Check the pool I/O time.

1. On FusionInsight Manager, choose O&M > Alarm > Alarms. In the alarm list, view the role name and obtain the IP address of the instance in Location of the alarm whose ID is 50840.
2. Choose Cluster > Services > MemArtsStore > Instances, click the StoreWorker instance for which the alarm is generated, and click the Chart tab of the instance.

   Select KV from Chart Category on the left, observe the KV SDK latency of the StoreWorker process, and check whether the latency decreases and the alarm is cleared.

   • If yes, no further action is required.
   • If no, go to Step 3.

Change the upper limit for concurrent Mempool service requests.

3. Log in to FusionInsight Manager, navigate to the MemArtsStore service, choose Configurations > All Configurations, and search for total_server_req_concurrent.
4. Locate the value of total_server_req_concurrent for MemArtsStore > StoreWorker.
   

   total_server_req_concurrent indicates the upper limit for a single Mempool node to process concurrent service requests. This alarm is generated when the number of service failures exceeds the threshold because the concurrent requests exceed this upper limit within the monitoring period (30 seconds).

5. Check whether this value is too small based on the actual concurrent service request processing capability of Mempool. If it is too small, increase it and click Save. Then the system modifies the configuration of all nodes synchronously.
6. Wait 2 minutes and check whether the alarm is automatically cleared.
   • If yes, no further action is required.
   • If no, go to Step 7.

Collect fault information.

7. On FusionInsight Manager, choose O&M. In the navigation pane on the left, choose Log > Download.
8. Expand the Service drop-down list, and select MemArtsStore for the target cluster.
9. Click the edit icon in the upper right corner, and set Start Date and End Date for log collection to 10 minutes ahead of and after the alarm generation time, respectively. Then, click Download.
10. Contact O&M engineers and send the collected logs.

Alarm Clearance

This alarm is automatically cleared after the fault is rectified.

Related Information

None