Azure-docs: Data limits -- how are bytes counted?

[rjmholt]

The data limits in documentation are specified in bytes, but JSON strings are encoding-dependent. And possibly compression-dependent.

If I need to know whether my data will be truncated on the client side, what test should I employ to determine this?

Do the byte sizes refer to what I've sent as a client, or do they depend on how these payloads are stored server-side by Azure?

Maximum of 30 MB per post to Azure Monitor Data Collector API. This is a size limit for a single post.

Is this the size limit of the entire UTF-8 encoded JSON body? What if I use Content-Encoding: gzip or similar (note this isn't Content-Type)?

Maximum of 32 KB limit for field values.

Is this the size of the JSON field encoded to UTF-8?

How is that size determined? For example, with { "myfield": "content" }, is this the number of bytes for:

• "myfield": "content"?
• "content"?
• content?

If I send a non-string JSON field, how many bytes does that represent? Is true 4 bytes? Is a number like 821.1 5 bytes or 8 (because IEEE 64-bit floating point) or something else? How many bytes does a date represent?

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• ID: 1295e1b3-5aed-3aee-4331-8b81e7a7e544
• Version Independent ID: 3c00a5ee-7093-1e8b-9004-8fed3f82960e
• Content: Azure Monitor HTTP Data Collector API
• Content Source: articles/azure-monitor/platform/data-collector-api.md
• Service: log-analytics
• GitHub Login: @bwren
• Microsoft Alias: bwren

[femsulu]

@rjmholt Thanks for your comment. We are actively investigating and will get back to you shortly. Thanks for your patience.

[femsulu]

Hi @rjmholt , sorry for the delay. After an internal review of your questions, we determined the Azure technical support will be the best team to provide the best possible response. Please use these steps to raise a support ticket. If you don't have a support plan, send mail to [email protected], include your subscription ID and a Link to this thread (for context) and my team will gladly assist you with engaging Azure support

[femsulu]

We will now close this issue. If there are further questions regarding this matter, please reply and we will gladly continue the discussion.

[rjmholt]

/cc @TravisEz13

Thanks for getting back to me.

I'll let @TravisEz13 decide on whether he wants to open a ticket.

If the documentation refers to a size limit for API calls, I think it needs to define how those sizes are calculated. I only need to know the answers to the size questions because those are the terms of reference used by the documentation; how else can any user of this API know if their call will exceed the limit?

Basically my issue isn't

Please answer these specific questions about the buffer sizes of your implementation.

It's

Please document the data limit semantics in a way that a client can usefully determine if they will hit those limits. And tell me what happens when I hit those limits (is the data truncated and a 200 returned, or is a 4XX returned with an error message, or ...?)

Basically, the failure mode is an important part of the API and needs to be documented in a way that a client application can work with it (e.g. know ahead of time if it will exceed the data limit).