zlacker

Anything you can "time nslookup" in or under 0.03 seconds (in "real" terms).

From my desk:

    local one - 0.029 seconds
    1.1.1.1 - 0.035 seconds
    8.8.8.8 - 0.120 seconds

Normally it should be, but Firefox's behavior is very sensitive to DNS response speed. Sounds not intuitive, but I think they're not using glibc's caching, or doing something by themselves.

>>bayind+(OP)
In the past, at least, firefox has done its own caching since expiring my OS dns cache was insufficient to get it to pick up a change in DNS.

>>bayind+(OP)
Tried it on a few sites, yeah, 8.8.8.8 consistently returns slower.

>>bayind+(OP)
Curious, where does this number comes from? (0.03 seconds)

>>jraph+wf
Nothing special. Just that if I have a DNS resolving around that timeframe, Firefox becomes noticeably faster.

All of the networks I have have a DNS server around that speed now, and Firefox works visibly faster on all of them. Possibly an intersection between human perception and hardware capabilities of my systems at hand.

>>aidenn+sb
Good reason to avoid Firefox for development imo. Nothing is more annoying than mysterious cache interventions when you're trying to get a handle on an unrelated problem.

>>CmdrKr+3r
Dev tools automatically disables caching for that tab, by default.

CTRL+SHIFT+R always disables cache for that reload, too.

>>bayind+oH
I didn't know about devtools doing that; C-S R is what I use when I run into it.

>>aidenn+KS
On the Dev Tools’ network tab, there should be a checkbox about it on the top left.

>>bayind+oH
In the dev tools settings there is a checkbox "Disable HTTP Cache (when toolbox is open)" which name seems to imply that this only applies to the resources that make up the page, not to DNS lookups (about:config name is devtools.cache.disabled, and it defaults to false).

I investigated and found that Firefox's in-memory DNS cache can be manually cleared by clicking a button in about:networking. To be fair Chrome also has a similar cache and method for clearing it. See: https://www.makeuseof.com/chrome-edge-firefox-safari-opera-b...

>>bayind+(OP)
> "time nslookup"

Or as a slightly more thorough approach, you can use something like namebench or dnsbench:

https://code.google.com/archive/p/namebench

https://github.com/askmediagroup/dnsbench

>>elisha+KQ1
Yeah, while it's not as thorough as these tools, the method is at least reproducible and sane, and with ~10 or so samples, you get an interval with a nice confidence.

Another through method will be hyperfine[0], yet I wanted to provide a method which requires no installation and can be done in a whim, without jumps and hoops, with the tools already at hand.

[0]: https://github.com/sharkdp/hyperfine