topic Re: Unknown latency source in Qlik Replicate

Unknown latency source

toanlc — Tue, 28 Oct 2025 14:08:09 GMT

I have setup monitoring based on Qlik Replicate Task PERFORMANCE logs and I can see one of my task (Logstream -> Snowflake) keep repeat the same pattern everyday where the latency kept on increasing (to couple hours) and then suddenly drop to less than 100 seconds. (Image below)

One thing makes it hard for me to understand is because source table has no changes for a while now but this pattern keeps on repeat.

May I ask how should I identify the source of latency in this case and should I base my monitoring on pending changes rather than PERFORMANCE data?

Thank you for your help

Re: Unknown latency source

Dana_Baldwin — Tue, 28 Oct 2025 20:14:27 GMT

Hi @toanlc

During this time of source latency on the child task, is there also latency on the parent task?

Does the parent task tables for this child task have a pattern of long running transactions before they are committed?

Thanks,

Dana

Re: Unknown latency source

toanlc — Wed, 29 Oct 2025 01:54:24 GMT

Hi @Dana_Baldwin,

Thanks for having a look.

When this happens, the parent task has almost no latency or just a few ms.

The table has only 86 rows and not been updated for a while now, so there is no commit to it.

Re: Unknown latency source

john_wang — Wed, 29 Oct 2025 02:17:56 GMT

Hello @toanlc ,

Thanks for the update.

Could you please check whether the task includes other tables, and if any of those tables have undergone significant changes?

Regards,

John.

Re: Unknown latency source

toanlc — Wed, 29 Oct 2025 03:08:24 GMT

Hi @john_wang,

I can confirm it's the only table on the parent task.