188505 - DNS: UI for DNS cache (dnsCacheExpiration, dnsCacheEntries)

Status: NEW

(SeaMonkey :: Preferences, enhancement)

Description

[Michael T. Babcock]

User-Agent:       Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.2.1) Gecko/20021130
Build Identifier: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.2.1) Gecko/20021130

Mozilla keeps an internal DNS cache that could be either superfluous (if the
user uses an OS that provides this functionality already) or damaging (if the
DNS records are set to expire before the cache expires them).

For the sake of the DNS record cache not honouring TTL, see bug 151929.

The DNS record cache should be by default set to 'enabled' to maintain the
current behaviour for most users, but it allows those users who know it is
unnecessary or slower than their OS implementation or to work around bugs in TTL
handling the ability to disable it.

Reproducible: Always

Steps to Reproduce:
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Actual Results:  
.

Expected Results:  
.

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Comment 1

[Boris Zbarsky [:bzbarsky]]

networking.

Comment 2

[benc]

+clean-report:

We don't seem to be making much progess in the other bug, so this might be the
next logical step until we work out the details.

People on really fast LANs and/or close to "well-connected" DNS servers don't
need the cache anyhow.

Comment 3

[Doug Turner (:dougt)]

-> gordon

Comment 4

[Dave Oftedal]

The DNS cache is preventing proper functionality.

Instead of going to the correct page when I've changed a defective DNS in
resolv.conf to a working one, mozilla deliberately seeks out the incorrect page
in an effort to maintain tradition. links, however, displays the correct page in
text only, not being a SUCKY BROWSER!

A very annoying "feature".

Comment 5

[Michael T. Babcock]

I'd like to point out for what its worth that I personally have absolutely no
need for a DNS cache in Mozilla as I use dnscache by DJB on my Linux machine at
home as well as my Linux gateway box at the office (which provides DNS resolver
services to my Windows boxes).

Whether some people need this functionality or not, the ability to shut it off
for those for whom it is broken or sub par or just a waste of effort seems
obvious.  I'm not sure what the huge delay in effort here is, besides perhaps votes.

If I could manage to get enough disk space on my home machine to compile this
thing from source, I might do it myself.

Comment 6

[Darin Fisher]

michael: you can disable mozilla's dns caching with the following prefs:

  user_pref("network.dnsCacheExpiration", 0);
  user_pref("network.dnsCacheEntries", 0);

if you want a UI option to make this easier to configure, then you will need to
file a bug with the respective owners of the browser UI.

we should either add controls for these prefs to the pref UI for the browser or
we should mark this bug WORKSFORME.

reassigning to Preferences component.

Comment 7

[Darin Fisher]

>if you want a UI option to make this easier to configure, then you will need to
>file a bug with the respective owners of the browser UI.

nevermind... reassigning this bug is good enough ;-)

Comment 8

[Wolfgang Rosenauer [:wolfiR]]

>   user_pref("network.dnsCacheExpiration", 0);
>   user_pref("network.dnsCacheEntries", 0);

these preferencer are not available in about:config?

Comment 9

[Darin Fisher]

that is correct, but that does not mean that you cannot add them yourself. 
preferences listed in about:config come from all.js or one of the other
preferences files.  the fact that you do not see the DNS prefs listed in
about:config means that they are not given default values in all.js.  they are
in effect "hidden" prefs.  the up side is that mozilla does not have to pay the
cost of loading these prefs when they are not defined.  instead, mozilla just
uses hardcoded default values when the preferences are not set.

Comment 10

[benc]

I've documented the prefs in:
http://www.mozilla.org/quality/networking/docs/netprefs.html

Comment 11

[Serge Gautherie (:sgautherie)]

(Filter "spam" on 'prefs-nobody-20080612'.)