Historizing tags

Hello everyone!

Does any knows what is the limit historizing tags with SQL Historian? and with the Historical Group?

Thanks! :thumb_left:

what sort of limit? number of tags? number of event per tag? minimum time between events? max time between events?

The answer for all of these is really ‘It depends’.

It depends on how fast your hardware is, how much disk space you have to store data, how good your selected database is at storing lots of data, how you partition the data,…

My experience with PostgreSQL has been that it can handle about 5,000,000 rows per table and then it starts slowing down.

Ignition does not impose limits so it really does depends and you have to trial it and see.

I’m trying to historize 160000 tags per second. Is this possible? what are the requirements (hardware) to do this?

:open_mouth: :open_mouth:

Hadoop? Cray? :smiling_imp:

Is that for one second, one minute, all day every day?

How many tags do you have? I know Kyle has posted about processing 27,000 changes a second. 160,000 changes a second would take a lot of processing power.

You might have to break it up. ie: have multiple history dbs each of which handle some of the total tags.

Let’s us know if you get it working and what it took. The IA guys will want to use it for marketing :smiley:

After 24 hours you’d have 13,824,000,000 rows (almost 14 BILLION). I’d say it’s time to look at your requirements again?

What matters from a computing perspective is how many writes/second you’re doing. Keep in mind that you can keep/log aggregate or statistical data, such as min/max/average values from your PLC(s). You can also use deadbands to log significant changes. Realistically, doing anything meaningful with that much data later will be a huge challenge.

If you do in fact have a huge data requirement, I would recommend contacting Kyle. He’s pretty savvy with hardware/software/OS/database tweaks. You won’t run into Ignition licensing problems, but you may have quite a system to engineer and a lot of data to maintain.

I will contact him. Basically I’m interested in knowing how should be the system (processor, ram, etc)
Thanks for your help!