latency in tables

[former_member252769]

Hello Gurus,

I have a issue with latencies in few table.

In our scenario, we are replicating around 400 tables and found 5 tables are in tolerable latency and 1 table in bad latency.

Though, the number of records in source and target are same.

There are total 20 WP available is system and in configuration 15 are Data transfer jobs and 5 are as Initial load jobs.

I checked previous discussions and but didn't helped much, How I can fix this latency issue?

Cheers

Brillion

[Former Member]

Hi,

When I was setting up our replication I got the SAP suggestion to use 1 job per 10 tables, that should keep the replication with really low latency - close to real time.

I think if you have the possibility to run 20 jobs then I would change the transfer jobs from 15 to 20 jobs. The initial load jobs are always taken from the number of transfer jobs. So if you need the 5 initial load jobs, you will still have 15 jobs for delta replication any other time 20 jobs will handle the delta replication.

Please make sure that SLT and also ERP can handle the higher load. 

I have had also cases that background jobs were pushing heavy data amount to the table and latency got worse during that time.

BR
Tamas

[former_member252769]

Hi Tamas,

Configuration is already having 12 transfer jobs out of 15 but latency is increasing in many other tables as well.

Actually, I started the replication for all the 400 tables at once. Is this the main issue?

Initially everything was fine and now many others tables are falling in latency.

How it can fix now now?

Regards

[Former Member]

Hi,

We have only 94 tables in replication using 10 data transfer jobs. The latency is around 0.5-2 seconds for tables with less then 10.000 operation per hours. 4-6 seconds for tables with operation more than 150.000 per hours. One bigger table with 500.000 operation per hour has latency of 6 seconds.

If I would reduce the number of transfer jobs to get on the 400 tables via 12 jobs ratio(2 jobs for the 94tables), I am sure the latency will raise a lot.

In my opinion you would need around 30jobs to handle 400 tables if the operations are on average 5000 per hours per table.

If you have many less frequently changing tables you could use less jobs, but in my opinion 12 jobs for 400 tables are not enough. This is my experience using SLT in customer environment.

Additional option could be to use filtering on SLT and limit the data what needs to be transferred if that is possible.

BR
Tamas

[Prabhith]

Hello,

Will you be able to provide the relevant info from ST03n/STAD workloads for the SLT system, which would help in doing a detailed analysis.

BR

Prabhith

[tobias_koebler]

Hi,

is the bad table a customer (z-)table or an SAP table? Have you massive batch import or something similar fot this table?

Best, Tobias

[former_member252769]

Hi Tobias,

Some are custom and some are SAP tables like ESTRH, ADRP etc.

Replication started for all the 400 tables at once. Initially everything was fine and now many others tables are falling in latency.

Replication at once is creating this issue? What is the best approach for loading tables, say batches of 10-15 tables or is it dependent on the number of jobs.

Can the latency is fixed now?

Regards