By "stack depth" I presume you mean "chain length"; each start/execute/finish runs in its own transaction and so has its own stack. I know of no absolute limit: chaining is very kind to the platform because things run in a sequence rather than in parallel. But worth some approximate calculations to see if you will run anywhere near this limit recognizing that each start/execute/finish counts as one of these:
Description The maximum number of asynchronous Apex method executions (batch Apex, future methods, Queueable Apex, and scheduled Apex) per a 24-hour period
Limit 250,000 or the number of user licenses in your org multiplied by 200, whichever is greater
https://salesforce.stackexchange.com/questions/230615/batch-apex-chaining-limits
https://force201.wordpress.com/2013/07/31/testing-a-database-batchable-implementation/
By "stack depth" I presume you mean "chain length"; each start/execute/finish runs in its own transaction and so has its own stack.
I know of no absolute limit: chaining is very kind to the platform because things run in a sequence rather than in parallel. But worth some approximate calculations to see if you will run anywhere near this limit recognizing that each start/execute/finish counts as one of these:
Description
The maximum number of asynchronous Apex method executions (batch Apex, future methods, Queueable Apex, and scheduled Apex) per a 24-hour period
Limit
250,000 or the number of user licenses in your org multiplied by 200, whichever is greater