virtualWrite limit per second

Please clarify the limit of virtual writes per second… is the absolute limit 10/s or something higher than that? Is this limit an average over some number of seconds (i.e. 10 within 1 sec, 20 with 2 s, etc?) or instantaneous (i.e. 1 every 0.1s)?

I want to do 20 virtualwrites every 2 seconds (actually would prefer every 1 second). All 20 of them would happen consecutively and rapidly in the timer loop which is triggered every 2 s. So there would be <0.1 s between writes within timer loop, but 10 writes/s on average over the 2 s timer interval. Is this OK?

Cant give you a straight answer, it comes down to maintaining a connection to the server. Cloud server has a limit of 10/s Where if you go over you get disconnected, if I recall correctly.

For your usage you should opt for a local server. It also boils down to what hardware you use I’d say.

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@davids as pointed out by @Fettkeewl there are so many factors involved that there isn’t a single answer. If you use those old Arduino things then expect a lower limit that those super fast ESP’s etc.

Are you not able to “consolidate” your data before upload to the server? Without knowing what you plan to do it’s hard to say but in most cases consolidation will work.

Thanks for the replies. I’m using nodemcu ESP8266, and would like to push updates of 20 integer values to 20 value display widgets in iOS Blynk app. I would like to have the update interval <=2 s. I don’t have a local server. If my initial approach wont work out, then I can try think of ways to consolidate or reduce my update frequency requirement.

Did you consider terminal widget? You could gather your data and update it every 2 seconds without issue. I’m having difficulty seeing that you could read/react to any quicker updates? Just let your hardware collect data then write to terminal every 2 seconds? Or are you in need of the history graph?

Guess you could always average reads instead. Depends on application of course

@davids are you able to say what this vital data actually does or is it classified info?

It’s possible that remote control vehicles or similar projects might need lots of data but most projects don’t have any problem with a virtualWrite limit.

@davids we have the limit on library side:

//Limit the amount of outgoing commands.
#define BLYNK_MSG_LIMIT 20

However, you may change it. But in most cases limitation is hardware.

Well I tried like I wanted it to work… With a 2 s timer interval, I was able to do 16 virtualwrites, an LED setColor, 2 lcd.prints, and an email notification (if occasionally triggered by a condition). I noticed in my serial monitor some semi-frequent error message about being disconnected and then immediately reconnecting. (I don’t remember the exact message and did not save it). Then I added in some small delay(50)'s in between the 16 virtual writes to spread them out a little within the timer function. I don’t see those disconnect/reconnecting messages anymore.

New problems (sorry if off topic):
For the email notification I had been using my email-to-text address It was working just fine for a couple days, but then suddenly stopped working on the notification condition. I thought it was flood related, which is why I then added the delay(50)'s mentioned above. Also I realized my code might have triggered a emails every 2 s if condition persisted (for a short duration <10~20 s)… So I added some logic to ensure no more than one email is triggered within 15 s. However after those changes the email to that address was still not working.

So I changed the email address to a different one and it works fine. I changed back to the address and it still does not work. Separately I verified that I can actually receive texts to this address, and I contacted AT&T and they said there are no blocks/filters/limits preventing any particular senders. Is there anything preventing Blynk server from sending emails to my address?

Also I tried using the Blynk notification in addition to the email. The Blynk notification also works as expected when the notify condition is met. However I noticed that I do not receive Blynk notification when hardware goes offline. Why not?

You are limited with 100 emails per day per account. This is stated in docs - See limits section.

Understood, but I don’t think I came close to 100 in 1 day. Maybe a few 10’s. It appears that messages requested to this particular address still aren’t being delivered. How to reset it?

You can’t. The counter will be reset after 24h after reaching a limit.

Thanks. I think it has been > 24 hr already since receiving the most recent email to the address in question before it stopped working; but I will try again to test it tonight and let you know. Yet my alternate email address seems to work presently. So I guess your limits must be address-specific, right?

What about blynk notifications… any daily limit for these? And any idea about my offline notification question?

The email notification is working again. Hardware offline blynk app notification is still not working. However condition triggered blynk app notification is working.