525921 - Would like a mechanism to disable or purge the DNS cache through JavaScript

Status: NEW

(Core :: Networking, defect, P3)

Description

[Rob Campbell [:rc] (:robcee)]

Currently, developers trying to figure out networking problems on their site have to contend with a full DNS cache. This can present problems when trying to debug some types of networking conditions. Would like to have a means to either clear the cache or a way to turn it off altogether.

Comment 1

[Christian :Biesinger (don't email me, ping me on IRC)]

file|work offline clears the cache

What do you mean with "have to contend with a full DNS cache"?

Also note that DNS cache entries are pretty shortlived.

Comment 2

[Rob Campbell [:rc] (:robcee)]

how short-lived?

I think the intent of this bug was to provide a way to set the DNS cache back to a clean state so developers could see what kind of round-trip time they were getting to their pages in a "cold" state. I wasn't aware of the "work offline" trick to clear those.

That might be a useful work-around if we don't want to provide an explicit option to dump those caches.

Comment 3

[Christian :Biesinger (don't email me, ping me on IRC)]

3 minutes by default (used to be 1 until we implemented DNS prefetching)

Is this just asking for exposing DNS cache clearing through XPCOM, or for actually exposing this to content script?

Comment 4

[Rob Campbell [:rc] (:robcee)]

(In reply to comment #3)
> 3 minutes by default (used to be 1 until we implemented DNS prefetching)

good to know, thanks.

> Is this just asking for exposing DNS cache clearing through XPCOM, or for
> actually exposing this to content script?

Just XPCOM so we could implement a control somewhere in the UI or in the console to forcibly purge the cache. Not a content thing.

Comment 5

[Firefox Bug Husbandry Bot]

Bulk change to priority: https://bugzilla.mozilla.org/show_bug.cgi?id=1399258

Comment 6

[Firefox Bug Husbandry Bot]

Bulk change to priority: https://bugzilla.mozilla.org/show_bug.cgi?id=1399258