91–100 of 313 posts
Bold of you to assume that there are system administrators. All too often these days it's "devops" aka some devs you taught how to write k8s yamls.
> When implementing logging, it's important to distinguish between an error from the perspective of an individual operation and an error from the perspective of the overall program or system. Individual operations may well experience errors that are not error level log events for the overall program. You could say that an operation error is anything that prevents an operation from completing successfully, while a pro…
> When implementing logging, it's important to distinguish between an error from the perspective of an individual operation and an error from the perspective of the overall program or system. Individual operations may well experience errors that are not error level log events for the overall program. You could say that an operation error is anything that prevents an operation from completing successfully, while a pro…
Libraries should not log, instead they should allow registering hooks which get called with errors and debug info.
> When implementing logging, it's important to distinguish between an error from the perspective of an individual operation and an error from the perspective of the overall program or system. Individual operations may well experience errors that are not error level log events for the overall program. You could say that an operation error is anything that prevents an operation from completing successfully, while a pro…
This is why it’s almost always wrong for library functions to log anything, even on ”errors”. Pass the status up through return values or exceptions. As a library author you have no clue as how an application might use it. Multi threading, retry loops and expected failures will turn what’s a significant event in one context into what’s not even worthy of a debug log in another. No rule without exceptions of course, o…
The application owner should be able to adjust the contexts up or down. This is the point of ownership and where responsibility over which logs matter is handled.
A library author might have ideas and provide useful suggestions, but it's ultimately the application owner who decides. Some libraries have huge blast radius and their `error` might be your `error` too. In other contexts, it could just be a warning. Library authors should make a reasonable guess about who their customer is and try to provide semantic, granular, and controllable failure behavior.
As an example, Rust's logging ecosystem provides nice facilities for fine-grained tamping down of errors by crate (library) or module name. Other languages and logging libraries let you do this as well.
That capability just isn't adopted everywhere.
How I'd personally like to treat them: - Critical / Fatal: Unrecoverable without human intervention, someone needs to get out of bed, now. - Error : Recoverable without human intervention, but not without data / state loss. Must be fixed asap. An assumption didn't hold. - Warning: Recoverable without intervention. Must have an issue created and prioritised. ( If business as usual, this could be downgrading to INFO. )…
> The main difference therefore between error and warning is, "We didn't think this could happen" vs "We thought this might happen". What about conditions like "we absolutely knew this would happen regularly, but it's something that prevents the completion of the entire process which is absolutely critical to the organization" The notion of an "error" is very context dependent. We usually use it to mean "can not proc…
In OpenStack, we explicitly document what our log levels mean; I think this is valuable from both an Operator and Developer perspective. If you're a new developer, without a sense of what log levels are for, it's very prescriptive and helpful. For an operator, it sets expectations. https://docs.openstack.org/oslo.log/latest/user/guidelines.h... FWIW, "ERROR: An error has occurred and an administrator should research…
Thank you, this (and jillesvangurp's comment) sounds way more reasonable than the article's suggestion. If I have a daily cron job that is copying files to a remote location (e.g. backups), and the _operation_ fails because for some reason the destination is not writable. Your suggestion would get me _both_ alerts, as I want; the article's suggestion would not alert me about the operation failing because, after all,…
> When implementing logging, it's important to distinguish between an error from the perspective of an individual operation and an error from the perspective of the overall program or system. Individual operations may well experience errors that are not error level log events for the overall program. You could say that an operation error is anything that prevents an operation from completing successfully, while a pro…
This is why it’s almost always wrong for library functions to log anything, even on ”errors”. Pass the status up through return values or exceptions. As a library author you have no clue as how an application might use it. Multi threading, retry loops and expected failures will turn what’s a significant event in one context into what’s not even worthy of a debug log in another. No rule without exceptions of course, o…
Earlier quoted context omitted.
hmm maybe we need extra representation? eg: 2.0 for "trace" / 1.0 for "debug" / 0.0 for "info" / -1.0 for "warn" / -2.0 for "error that can be handled"
I said this elsewhere, but the point here is what the humans involved are supposed to do with this info. Do I literally get out of bed on an error log or do I grep for them once or twice a month?
How I'd personally like to treat them: - Critical / Fatal: Unrecoverable without human intervention, someone needs to get out of bed, now. - Error : Recoverable without human intervention, but not without data / state loss. Must be fixed asap. An assumption didn't hold. - Warning: Recoverable without intervention. Must have an issue created and prioritised. ( If business as usual, this could be downgrading to INFO. )…